AFLAC INC, 10-K filed on 2/23/2022
Annual Report
v3.22.0.1
Document and Entity Information - USD ($)
 12 Months Ended
Dec. 31, 2021
Feb. 16, 2022
Jun. 30, 2021
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2021    
Document Transition Report false    
Entity File Number 001-07434    
Entity Registrant Name Aflac Incorporated    
Entity Incorporation, State or Country Code GA    
Entity Tax Identification Number 58-1167100    
Entity Address, Address Line One 1932 Wynnton Road    
Entity Address, City or Town Columbus    
Entity Address, State or Province GA    
Entity Address, Postal Zip Code 31999    
City Area Code 706    
Local Phone Number 323.3431    
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
Entity Shell Company false    
Entity Public Float     $ 35,892,975,941
Entity Common Stock, Shares Outstanding   649,860,875  
Amendment Flag false    
Entity Central Index Key 0000004977    
Current Fiscal Year End Date --12-31    
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2021    
ICFR Auditor Attestation Flag true    
Documents Incorporated by Reference Certain information contained in the Notice and Proxy Statement for the Company’s 2022 Annual Meeting of Shareholders is incorporated by reference into Part III hereof.    
Auditor Name KPMG LLP    
Auditor Firm ID 185    
Auditor Location Atlanta, Georgia    
NEW YORK STOCK EXCHANGE, INC.      
Title of 12(b) Security Common Stock, $.10 Par Value    
Trading Symbol AFL    
Security Exchange Name NYSE    
v3.22.0.1
Consolidated Statements of Earnings - USD ($)
shares in Thousands, $ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Revenues:      
Net earned premiums, principally supplemental health insurance $ 17,647 $ 18,622 $ 18,780
Net investment income 3,818 3,638 3,578
Net investment gains (losses) 468 (270) (135)
Other income (loss) 173 157 84
Total revenues 22,106 22,147 22,307
Benefits and expenses:      
Benefits and claims, net 10,576 11,796 11,942
Acquisition and operating expenses:      
Amortization of deferred policy acquisition costs 1,170 1,214 1,282
Insurance commissions 1,256 1,316 1,321
Insurance and other expenses [1] 3,544 3,420 3,089
Interest expense 238 242 228
Total acquisition and operating expenses 6,208 6,192 5,920
Total benefits and expenses 16,784 17,988 17,862
Earnings before income taxes 5,322 4,159 4,445
Income Tax Expense:      
Current 1,095 794 806
Deferred (98) (1,413) 335
Total income tax expense 997 (619) 1,141
Net earnings $ 4,325 $ 4,778 $ 3,304
Net earnings per share:      
Basic (in dollars per share) $ 6.42 $ 6.69 $ 4.45
Diluted (in dollars per share) $ 6.39 $ 6.67 $ 4.43
Weighted-average outstanding common shares used in computing earnings per share (In thousands):      
Basic (in shares) 673,617 713,702 742,414
Diluted (in shares) 676,729 716,192 746,430
Cash dividends per share $ 1.32 $ 1.12 $ 1.08
[1] Includes expense of $48 in 2021 and $15 in 2020 for the early extinguishment of debt.
v3.22.0.1
Consolidated Statements of Earnings (Parenthetical) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
3.625% senior notes paid May 2021    
Expense on extinguishment of debt $ 48  
4.00% senior notes paid January 2020    
Expense on extinguishment of debt   $ 15
v3.22.0.1
Consolidated Statements of Comprehensive Income (Loss) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Statement of Comprehensive Income [Abstract]      
Net earnings $ 4,325 $ 4,778 $ 3,304
Other comprehensive income (loss) before income taxes:      
Unrealized foreign currency translation gains (losses) during period (889) 510 252
Unrealized gains (losses) on fixed maturity securities:      
Unrealized holding gains (losses) on fixed maturity securities during period (929) 1,061 5,870
Reclassification adjustment for (gains) losses on fixed maturity securities included in net earnings (31) 159 (18)
Unrealized gains (losses) on derivatives during period 5 (1) (12)
Pension liability adjustment during period 148 (7) (85)
Total other comprehensive income (loss) before income taxes (1,696) 1,722 6,007
Income tax expense (benefit) related to items of other comprehensive income (loss) (155) 251 1,543
Other comprehensive income (loss), net of income taxes (1,541) 1,471 4,464
Total comprehensive income (loss) $ 2,784 $ 6,249 $ 7,768
v3.22.0.1
Consolidated Balance Sheets - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Investments and cash:    
Available for sale, fixed maturity securities $ 98,696 $ 105,882
Held to maturity fixed maturity securities, net carrying amount 22,000 [1] 24,464
Equity securities 1,603 1,283
Commercial mortgage and other loans 11,786 10,554
Other investments 3,842 2,429
Cash and cash equivalents 5,051 5,141
Total investments and cash 142,978 149,753
Receivables 693 796
Accrued investment income 737 780
Deferred policy acquisition costs 9,525 10,441
Property and equipment, at cost less accumulated depreciation 538 601
Other 3,071 2,715
Assets 157,542 165,086
Policy liabilities:    
Future policy benefits 90,588 97,783
Unpaid policy claims 4,836 5,187
Unearned premiums 2,576 3,597
Other policyholders' funds 7,072 7,824
Total policy liabilities 105,072 114,391
Income taxes 4,339 4,661
Payables for return of cash collateral on loaned securities 2,162 964
Notes payable and lease obligations 7,956 7,899
Other 4,760 3,612
Total liabilities 124,289 131,527
Commitments and contingent liabilities (Note 15)
Shareholders' equity:    
Common stock of $.10 par value. In thousands: authorized 1,900,000 shares in 2021 and 2020; issued 1,352,739 shares in 2021 and 1,351,018 shares in 2020 135 135
Additional paid-in capital 2,529 2,410
Retained earnings 41,381 37,984
Accumulated other comprehensive income (loss):    
Unrealized foreign currency translation gains (losses) (2,013) (1,109)
Unrealized gains (losses) on fixed maturity securities 9,602 10,361
Unrealized gains (losses) on derivatives (30) (34)
Pension liability adjustment (166) (284)
Treasury stock, at average cost (18,185) (15,904)
Total shareholders' equity 33,253 33,559
Total liabilities and shareholders' equity 157,542 165,086
Consolidated Entity Excluding Variable Interest Entities (VIE)    
Investments and cash:    
Available for sale, fixed maturity securities 94,206 101,286
Variable Interest Entity, Consolidated    
Investments and cash:    
Available for sale, fixed maturity securities 4,490 4,596
Commercial mortgage and other loans [2] 9,740 8,964
Other investments [2],[3] 1,535 826
Policy liabilities:    
Total liabilities [2] $ 414 $ 231
[1] Net of allowance for credit losses
[2] Net of allowance for credit losses
[3] Consists entirely of alternative investments in limited partnerships
v3.22.0.1
Consolidated Balance Sheets (Parenthetical) - USD ($)
shares in Thousands, $ in Millions
Dec. 31, 2021
Dec. 31, 2020
Available for sale, fixed maturity securities, allowance for credit losses $ 0 $ 38
Available for sale, fixed maturity securities, amortized cost 85,369 91,630
Held-to-maturity, fixed maturity securities, allowance for credit losses 8 10
Held to maturity, fixed maturity securities, fair value 26,869 30,399
Commercial mortgage and other loans, allowance for credit losses 174 180
Commercial mortgage and other loans 11,786 10,554
Other investments $ 3,842 $ 2,429
Common stock, par value (in dollars per share) $ 0.10 $ 0.10
Common stock, shares authorized (in shares) 1,900,000 1,900,000
Common stock, shares issued (in shares) 1,352,739 1,351,018
Consolidated Entity Excluding Variable Interest Entities (VIE)    
Available for sale, fixed maturity securities, allowance for credit losses $ 0 $ 38
Available for sale, fixed maturity securities, amortized cost 82,105 88,143
Variable Interest Entity, Consolidated    
Available for sale, fixed maturity securities, amortized cost [1] 3,264 3,487
Commercial mortgage and other loans [1] 9,740 8,964
Other investments [1],[2] $ 1,535 $ 826
[1] Net of allowance for credit losses
[2] Consists entirely of alternative investments in limited partnerships
v3.22.0.1
Consolidated Statements of Shareholders' Equity - USD ($)
$ in Millions
Total
Cumulative effect, period of adoption, adjustment
Cumulative effect, period of adoption, adjusted balance
Common stock
Common stock
Cumulative effect, period of adoption, adjustment
Common stock
Cumulative effect, period of adoption, adjusted balance
Additional paid-in capital
Additional paid-in capital
Cumulative effect, period of adoption, adjustment
Additional paid-in capital
Cumulative effect, period of adoption, adjusted balance
Retained earnings
Retained earnings
Cumulative effect, period of adoption, adjustment
Retained earnings
Cumulative effect, period of adoption, adjusted balance
Accumulated other comprehensive income (loss)
Accumulated other comprehensive income (loss)
Cumulative effect, period of adoption, adjustment
Accumulated other comprehensive income (loss)
Cumulative effect, period of adoption, adjusted balance
Treasury stock
Treasury stock
Cumulative effect, period of adoption, adjustment
Treasury stock
Cumulative effect, period of adoption, adjusted balance
Balance, beginning of period at Dec. 31, 2018 $ 23,462     $ 135     $ 2,177     $ 31,788     $ 2,151     $ (12,789)    
Increase (Decrease) in Stockholders' Equity [Roll Forward]                                    
Net earnings 3,304     0     0     3,304     0     0    
Unrealized foreign currency translation gains (losses) during period, net of income taxes 224     0     0     0     224     0    
Unrealized gains (losses) on fixed maturity securities during the period, net of income taxes and reclassification adjustments 4,314     0     0     0     4,314     0    
Unrealized gains (losses) on derivatives during period, net of income taxes (9)     0     0     0     (9)     0    
Pension liability adjustment during period, net of income taxes (65)     0     0     0     (65)     0    
Dividends to shareholders [1] (801)     0     0     (801)     0     0    
Exercise of stock options 29     0     29     0     0     0    
Share-based compensation 54     0     54     0     0     0    
Purchases of treasury stock (1,656)     0     0     0     0     (1,656)    
Treasury stock reissued 103     0     53     0     0     50    
Balance, end of period at Dec. 31, 2019 28,959   $ 29,751 135   $ 135 2,313   $ 2,313 34,291   $ 34,235 6,615   $ 7,463 (14,395)   $ (14,395)
Balance, end of period (Accounting Standards Update 2016-13) at Dec. 31, 2019 [2]   $ (56)     $ 0     $ 0     $ (56)     $ 0     $ 0  
Balance, end of period (Accounting Standards Update 2019-04) at Dec. 31, 2019 [2]   $ 848     $ 0     $ 0     $ 0     $ 848     $ 0  
Increase (Decrease) in Stockholders' Equity [Roll Forward]                                    
Net earnings 4,778     0     0     4,778     0     0    
Unrealized foreign currency translation gains (losses) during period, net of income taxes 514     0     0     0     514     0    
Unrealized gains (losses) on fixed maturity securities during the period, net of income taxes and reclassification adjustments 965     0     0     0     965     0    
Unrealized gains (losses) on derivatives during period, net of income taxes (1)     0     0     0     (1)     0    
Pension liability adjustment during period, net of income taxes (7)     0     0     0     (7)     0    
Dividends to shareholders [1] (1,029)     0     0     (1,029)     0     0    
Exercise of stock options 12     0     12     0     0     0    
Share-based compensation 53     0     53     0     0     0    
Purchases of treasury stock (1,565)     0     0     0     0     (1,565)    
Treasury stock reissued 88     0     32     0     0     56    
Balance, end of period at Dec. 31, 2020 33,559     135     2,410     37,984     8,934     (15,904)    
Increase (Decrease) in Stockholders' Equity [Roll Forward]                                    
Net earnings 4,325     0     0     4,325     0     0    
Unrealized foreign currency translation gains (losses) during period, net of income taxes (904)     0     0     0     (904)     0    
Unrealized gains (losses) on fixed maturity securities during the period, net of income taxes and reclassification adjustments (759)     0     0     0     (759)     0    
Unrealized gains (losses) on derivatives during period, net of income taxes 4     0     0     0     4     0    
Pension liability adjustment during period, net of income taxes 118     0     0     0     118     0    
Dividends to shareholders [1] (928)     0     0     (928)     0     0    
Exercise of stock options 18     0     18     0     0     0    
Share-based compensation 61     0     61     0     0     0    
Purchases of treasury stock (2,322)     0     0     0     0     (2,322)    
Treasury stock reissued 81     0     40     0     0     41    
Balance, end of period at Dec. 31, 2021 $ 33,253     $ 135     $ 2,529     $ 41,381     $ 7,393     $ (18,185)    
[1] Dividends to shareholders are recorded in the period in which they are declared.
[2] See Note 1 of the Notes to the Consolidated Financial Statements for the adoption of accounting guidance on January 1, 2020.
v3.22.0.1
Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Retained earnings      
Dividends to shareholders (in dollars per share) $ 1.39 $ 1.45 $ 1.08
v3.22.0.1
Consolidated Statements of Cash Flows - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Cash flows from operating activities:      
Net earnings $ 4,325 $ 4,778 $ 3,304
Adjustments to reconcile net earnings to net cash provided by operating activities:      
Change in receivables and advance premiums 72 52 (32)
Capitalization of deferred policy acquisition costs (1,063) (1,142) (1,452)
Amortization of deferred policy acquisition costs 1,170 1,214 1,282
Increase in policy liabilities 976 2,023 2,104
Change in income tax liabilities 118 (1,419) (244)
Net investment (gains) losses (468) 270 135
Other, net (79) 182 358
Net cash provided (used) by operating activities 5,051 5,958 5,455
Proceeds from investments sold or matured:      
Available-for-sale fixed maturity securities 4,157 3,725 5,284
Equity securities 264 234 650
Held-to-maturity fixed maturity securities 4 4 622
Commercial mortgage and other loans 4,099 2,085 1,814
Costs of investments acquired:      
Available for sale fixed maturity securities (5,813) (4,772) (6,934)
Equity securities (492) (498) (347)
Commercial mortgage and other loans (5,282) (3,263) (4,401)
Other investments, net (1,066) (860) (653)
Settlement of derivatives, net 199 18 (9)
Cash received (pledged or returned) as collateral, net 1,511 (1,027) 926
Other, net 41 (265) (123)
Net cash provided (used) by investing activities (2,378) (4,619) (3,171)
Cash flows from financing activities:      
Purchases of treasury stock (2,301) (1,537) (1,627)
Proceeds from borrowings 1,153 1,545 615
Principal payments under debt obligations (700) (350) 0
Dividends paid to shareholders (855) (769) (771)
Change in investment-type contracts, net (36) (11) (1)
Treasury stock reissued 26 34 49
Other, net (26) (27) 22
Net cash provided (used) by financing activities (2,739) (1,115) (1,713)
Effect of exchange rate changes on cash and cash equivalents (24) 21 (12)
Net change in cash and cash equivalents (90) 245 559
Cash and cash equivalents, beginning of period 5,141 4,896 4,337
Cash and cash equivalents, end of period 5,051 5,141 4,896
Supplemental disclosures of cash flow information:      
Income taxes paid 880 800 1,384
Interest paid 213 210 190
Noncash interest 24 32 37
Noncash financing activities:      
Lease obligations 46 56 132
Associate stock bonus      
Treasury stock issued for:      
Treasury stock issued 19 19 15
Shareholder dividend reinvestment      
Treasury stock issued for:      
Treasury stock issued 32 29 30
Share-based compensation grants      
Treasury stock issued for:      
Treasury stock issued $ 4 $ 6 $ 5
v3.22.0.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
 12 Months Ended
Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Description of Business 
Aflac Incorporated (the Parent Company) and its subsidiaries (collectively, the Company) primarily sell supplemental health and life insurance in the United States (U.S.) and Japan. The Company's insurance business is marketed and administered through American Family Life Assurance Company of Columbus (Aflac) in the U.S. and through Aflac Life Insurance Japan Ltd. (ALIJ) in Japan. The Company’s operations consist of two reportable business segments: Aflac U.S., which includes Aflac, and Aflac Japan, which includes ALIJ. American Family Life Assurance Company of New York (Aflac New York) is a wholly owned subsidiary of Aflac. Most of Aflac's policies are individually underwritten and marketed through independent agents.With the exception of dental and vision products administered by Argus Dental & Vision, Inc. (Argus) and certain group life insurance products, Aflac U.S. markets and administers group products through Continental American Insurance Company (CAIC), branded as Aflac Group Insurance. The Company's insurance operations in the U.S. and Japan service the two markets for the Company's insurance business. Aflac Japan's revenues, including net gains and losses on its investment portfolio, accounted for 69% of the Company's total revenues in 2021, compared with 68% in 2020 and 69% in 2019. The percentage of the Company's total assets attributable to Aflac Japan was 82% at December 31, 2021, compared with 83% at December 31, 2020.

In November 2020, the Company, through its insurance subsidiaries Aflac and Aflac New York, acquired Zurich North America’s U.S. Corporate Life and Pensions business (Zurich), which consists of group life, disability and absence management products. Aflac and Aflac New York will reinsure on an indemnity basis Zurich's in-force group life and disability policies. Aflac also acquired assets needed to support the group life and disability business, along with an absence management platform.

In November 2019, the Company acquired Argus Holdings, LLC and its subsidiary Argus Dental & Vision, Inc. (Argus), a benefits management organization and national network dental and vision company, which provides a platform for Aflac Dental and Vision. Argus is an addition to the Aflac U.S. segment.

Basis of Presentation
The Company prepares its financial statements in accordance with U.S. generally accepted accounting principles (U.S. GAAP). These principles are established primarily by the Financial Accounting Standards Board (FASB). In these Notes to the Consolidated Financial Statements, references to U.S. GAAP issued by the FASB are derived from the FASB Accounting Standards CodificationTM (ASC). The preparation of financial statements in conformity with U.S. GAAP requires the Company to make estimates based on currently available information when recording transactions resulting from business operations. The most significant items on the Company's balance sheet that involve a greater degree of accounting estimates and actuarial determinations subject to changes in the future are the valuation of investments and derivatives, deferred policy acquisition costs (DAC), liabilities for future policy benefits and unpaid policy claims, and income taxes. These accounting estimates and actuarial determinations are sensitive to market conditions, investment yields, mortality, morbidity, commission and other acquisition expenses, and terminations by policyholders. As additional information becomes available, or actual amounts are determinable, the recorded estimates are revised and reflected in operating results. Although some variability is inherent in these estimates, the Company believes the amounts provided are reasonable and reflective of the best estimates of management.

The consolidated financial statements include the accounts of the Parent Company, its subsidiaries, and those entities required to be consolidated under applicable accounting standards. All material intercompany accounts and transactions have been eliminated.

Coronavirus Disease 2019 (COVID-19): The impact of the COVID-19 global pandemic on the Company continues to evolve. Both Aflac Japan and Aflac U.S. have taken measures to address employee health and safety and increase employees’ ability to develop and maintain more flexible working conditions, with return to office undertaken as warranted by local conditions, and operations have remained stable throughout 2021. The Company continues to monitor its investment portfolios to adjust to market conditions, including the continuing recovery, changes in monetary policy and inflation. Both Aflac Japan and Aflac U.S. have accelerated investments in digital initiatives to improve productivity, efficiency and customer service over the long term.
The Company also continues to closely monitor the effects and risks of COVID-19 to assess its impact on economic conditions in Japan and the U.S. and on the Company's business, financial condition, results of operations, liquidity and capital position.

Significant Accounting Policies

Foreign Currency Translation: The functional currency of Aflac Japan is the Japanese yen. The Company translates its yen-denominated financial statement accounts into U.S. dollars as follows. Assets and liabilities are translated at end-of-period exchange rates. Realized gains and losses on security transactions are translated at the exchange rate on the trade date of each transaction. Other revenues, expenses, and cash flows are translated using average exchange rates for the period. The resulting currency translation adjustments are reported in accumulated other comprehensive income. The Company includes in earnings the realized currency exchange gains and losses resulting from foreign currency transactions.

The Parent Company has designated a majority of its yen-denominated liabilities (notes payable and yen-denominated loans) as non-derivative hedges and from time-to-time may designate certain foreign currency forwards and options as derivative hedges of the foreign currency exposure of the Company's net investment in Aflac Japan. Outstanding principal and related accrued interest on these Parent Company liabilities and the fair value of these derivatives are translated into U.S. dollars at end-of-period exchange rates. Currency translation adjustments and changes in the fair value of these derivatives are recorded as unrealized foreign currency translation gains (losses) in other comprehensive income and are included in accumulated other comprehensive income.

Insurance Revenue and Expense Recognition: Substantially all of the supplemental health and life insurance policies the Company issues are classified as long-duration contracts. The contract provisions generally cannot be changed or canceled during the contract period; however, the Company may adjust premiums for supplemental health policies issued in the U.S. within prescribed guidelines and with the approval of state insurance regulatory authorities.

Insurance premiums for most of the Company's health and life policies, including cancer, accident, hospital, critical illness, dental, vision, term life, whole life, long-term care and disability, are recognized as earned premiums over the premium-paying periods of the contracts when due from policyholders. When earned premiums are reported, the related amounts of benefits and expenses are charged against such revenues, so that profits are recognized in proportion to earned premiums during the period the policies are expected to remain in force. This association is accomplished by means of annual additions to the liability for future policy benefits and the deferral and subsequent amortization of policy acquisition costs.

Premiums from the Company's products with limited-pay features, including term life, whole life, WAYS, and child endowment, are collected over a significantly shorter period than the period over which benefits are provided. Premiums for these products are recognized as earned premiums over the premium-paying periods of the contracts when due from policyholders. Any gross premium in excess of the net premium is deferred and recorded in earnings, such that profits are recognized in a constant relationship with insurance in force. Benefits are recorded as an expense when they are incurred. A liability for future policy benefits is recorded when premiums are recognized using the net premium method.

At the policyholder's option, customers can also pay discounted advanced premiums for certain of the Company's products. Advanced premiums are deferred and recognized when due from policyholders over the regularly scheduled premium payment period.

The calculation of DAC and the liability for future policy benefits requires the use of estimates based on sound actuarial valuation techniques. For new policy issues, the Company reviews its actuarial assumptions and deferrable acquisition costs each year and revises them when necessary to more closely reflect recent experience and studies of actual acquisition costs. For policies in force, the Company evaluates DAC by major product groupings to determine that they are recoverable from future revenues, and any amounts determined not to be recoverable are charged against net earnings. The Company has not had any material charges to earnings for DAC that was determined not to be recoverable in any of the years presented in this Form 10-K.

Advertising expense is reported as incurred in insurance expenses in the consolidated statements of earnings.

Cash and Cash Equivalents: Cash and cash equivalents include cash on hand, money market instruments, and other debt instruments with a maturity of 90 days or less when purchased.
Investments: The Company's debt securities consist of fixed maturity securities, which are classified as either held to maturity or available for sale. Securities classified as held to maturity are securities that the Company has the ability and intent to hold to maturity or redemption and are carried at amortized cost.

All other fixed maturity debt securities are classified as available for sale and are carried at fair value. If the fair value is higher than the amortized cost for debt securities, the excess is an unrealized gain, and if lower than cost, the difference is an unrealized loss. The net unrealized gains and losses on securities available for sale, less related deferred income taxes, are recorded through other comprehensive income and included in accumulated other comprehensive income.

Amortized cost of debt securities is based on the Company's purchase price adjusted for accrual of discount, or amortization of premium, and recognition of impairment charges, if any. The amortized cost of debt securities the Company purchases at a discount or premium will equal the face or par value at maturity or the call date, if applicable. Interest is reported as income when earned and is adjusted for amortization of any premium or discount.

The Company has investments in marketable equity securities which are carried at fair value. Changes in the fair value of equity securities are recorded in earnings as a component of net investment gains and losses.

The Company has investments in variable interest entities (VIEs). Criteria for evaluating VIEs for consolidation focuses on identifying which enterprise has the power to direct the activities of a variable interest entity that most significantly impact the entity's economic performance and (1) the obligation to absorb losses of the entity or (2) the right to receive benefits from the entity. The Company is the primary beneficiary of certain VIEs, and therefore consolidates these entities in its financial statements. While the consolidated VIEs generally operate within a defined set of contractual terms, there are certain powers that are retained by the Company that are considered significant in the conclusion that the Company is the primary beneficiary. These powers vary by structure but generally include the initial selection of the underlying collateral; the ability to obtain the underlying collateral in the event of default; and, the ability to appoint or dismiss key parties in the structure. In particular, the Company's powers surrounding the underlying collateral were considered to be the most significant powers because these most significantly impact the economics of the VIE. The Company has no obligation to provide any continuing financial support to any of the entities in which it is the primary beneficiary. The Company's maximum loss is limited to its original investment. Neither the Company nor any of its creditors have the ability to obtain the underlying collateral, nor does the Company have control over the instruments held in the VIEs, unless there is an event of default. For those entities where the Company is the primary beneficiary, the consolidated entity's assets are segregated on the balance sheet by the caption "consolidated variable interest entities," and consist of fixed maturity securities, equity securities, loan receivables, limited partnerships and derivative instruments.

For the mortgage- and asset-backed securities held in the Company's fixed maturity portfolio, the Company recognizes income using a constant effective yield, which is based on anticipated prepayments and the estimated economic life of the securities. When estimates of prepayments change, the effective yield is recalculated to reflect actual payments to date and anticipated future payments. The net investment in mortgage- and asset-backed securities is adjusted to the amount that would have existed had the new effective yield been applied at the time of acquisition. This adjustment is reflected in net investment income.

The Company uses the specific identification method to determine the gain or loss from securities transactions and report the realized gain or loss in the consolidated statements of earnings as net investment gain or loss. Securities transactions are accounted for based on values as of the trade date of the transaction.

The Company lends fixed maturity and public equity securities to financial institutions in short-term security-lending transactions. These securities continue to be carried as investment assets on the Company's balance sheet during the terms of the loans and are not reported as sales. The Company receives cash or other securities as collateral for such loans. For loans involving unrestricted cash or securities as collateral, the collateral is reported as an asset with a corresponding liability for the return of the collateral. For loans where the Company receives as collateral securities that the Company is not permitted to sell or repledge, the collateral is not reported as an asset.

Commercial mortgage and other loans include transitional real estate loans (TREs), commercial mortgage loans (CMLs) and middle market loans (MMLs). The Company's investments in TREs, CMLs, and MMLs are accounted for as loan receivables and are recorded at amortized cost on the acquisition date. The Company has the intent and ability to hold these loan receivables for the foreseeable future or until they mature and therefore, they are considered held for investment and are carried at amortized cost in the commercial mortgage and other loans line in its consolidated balance sheets. The amortized cost of the loan receivables reflects allowances for expected lifetime losses estimated as of each reporting date.
Other investments include policy loans, limited partnerships, and short-term investments with maturities at the time of purchase of one year or less, but greater than 90 days. Limited partnerships are accounted for using the equity method of accounting. Under the equity method of accounting, the Company reports its proportionate share of the investee's earnings or losses as a component of net investment income in its consolidated statements of earnings. The underlying investments held by the Company’s limited partnerships primarily consist of private equity and real estate. Short-term investments are stated at amortized cost, which approximates fair value.

Credit Losses: The Company estimates expected lifetime credit losses on financial assets measured at amortized cost including short-term receivables, premiums receivable, held-to-maturity fixed maturity securities, loan receivables, loan commitments and reinsurance recoverables. For available-for-sale fixed maturity securities, the Company evaluates estimated credit losses only when the fair value of the available-for-sale fixed maturity security is below its amortized cost basis. Credit loss changes are recorded as a component of net investment gains and losses for the Company’s held-to-maturity and available-for-sale securities, loan receivables, loan commitments and reinsurance recoverables, whereas credit losses on premium receivables are recorded in net earned premiums in the consolidated statement of earnings. The Company’s off-balance sheet credit exposure is primarily attributable to loan commitments that are not unconditionally cancellable. The Company considers the contractual period of exposure to credit risk, the likelihood that funding will occur, the risk of loss, and the current conditions and expectations of future economic conditions to develop the estimate of expected credit losses. The Company records the estimate of expected credit losses for certain loan commitments within other liabilities in the consolidated balance sheet.

Write-offs and partial write-offs are recorded as a reduction to the amortized cost of the loan or fixed maturity security balance and a corresponding reduction to the credit allowance.

The Company has elected not to measure an allowance on accrued interest income for all asset types, because the uncollectible accrued interest receivable is written off in a timely manner. The Company writes off accrued interest when it is more than ninety days past due by reducing interest income, which is a component of net investment income, in the consolidated statement of earnings.

The Company records due premium receivable net of current expected credit losses in the receivables line item in the consolidated balance sheet, utilizing an aging methodology based on historical loss information, adjusted for current conditions and reasonable and supportable forecasts. Changes in the estimated credit losses related to premium receivable are recorded in net earned premiums in the consolidated statement of earnings.

Prior to January 1, 2020, the Company followed other-than-temporary impairment (OTTI) guidance for its fixed maturity securities to recognize and measure OTTIs for its held-to-maturity and available-for-sale securities. For loans and loan receivables, the amortized cost reflected allowances for expected incurred losses based on past events and current economic conditions as of each reporting date.

Derivatives and Hedging: Freestanding derivative instruments are reported in the consolidated balance sheet at fair value and are reported in other assets and other liabilities, with changes in value reported in earnings and/or other comprehensive income. These freestanding derivatives are foreign currency forwards, foreign currency options, foreign currency swaps, interest rate swaps and interest rate swaptions. The Company does not use derivatives for trading purposes, nor does the Company engage in leveraged derivative transactions.

From time to time, the Company purchases certain investments that contain an embedded derivative. The Company assesses whether this embedded derivative is clearly and closely related to the asset that serves as its host contract. If the Company deems that the embedded derivative's terms are not clearly and closely related to the host contract, and a separate instrument with the same terms would qualify as a derivative instrument, the derivative is separated from that contract, held at fair value, and reported with the host instrument in the consolidated balance sheet, with changes in fair value reported in earnings. If the Company has elected the fair value option, the embedded derivative is not bifurcated, and the entire investment is held at fair value with changes in fair value reported in earnings.
See Note 5 for a discussion on how the Company determines the fair value of its derivatives. Accruals on derivatives are typically recorded in other assets or within other liabilities in the consolidated balance sheets.

To qualify for hedge accounting treatment, a derivative must be highly effective in mitigating the designated risk attributable to the hedged item. At the inception of hedging relationships the Company formally documents all relationships between hedging instruments and hedged items, as well as its risk-management objectives and strategies for undertaking the respective hedging relationship, and the methodology that will be used to assess the effectiveness of the hedge relationship at and subsequent to hedge inception. The Company documents the designation of each hedge as
either (i) a hedge of the variability of cash flows to be received or paid related to a recognized asset or liability or the hedge of a forecasted transaction ("cash flow hedge"); (ii) a hedge of the estimated fair value of a recognized asset or liability ("fair value hedge"); or (iii) a hedge of a net investment in a foreign operation ("net investment hedge"). The documentation process includes linking derivatives and non-derivative financial instruments that are designated as hedges to specific assets or groups of assets or liabilities in the statement of financial position or to specific forecasted transactions and defining the effectiveness testing methods to be used. At the hedge inception and on an ongoing quarterly basis, the Company also formally assesses whether the derivatives and non-derivative financial instruments used in hedging activities have been, and are expected to continue to be, highly effective in offsetting their designated risk. Hedge effectiveness is assessed using qualitative and quantitative methods. The assessment of hedge effectiveness determines the accounting treatment of changes in fair value.
For assessing hedge effectiveness, qualitative methods may include the comparison of critical terms of the derivative to the hedged item, and quantitative methods may include regression, dollar offset, or other statistical analysis of changes in fair value or cash flows associated with the hedge relationship.
For derivative instruments that are designated and qualify as cash flow hedges, the effective portion of the gain or loss on the derivative is reported as a component of accumulated other comprehensive income (loss) and reclassified into earnings in the same period or periods during which the hedged transaction affects earnings. In cash flow hedges, all components of each derivative's gain or loss are included in the assessment of hedge effectiveness. The ineffective portion of the change in the fair value of the derivative is recognized in earnings when it occurs.
For derivative instruments that are designated and qualify as fair value hedges, the gain or loss on the hedged item and the portion of the hedging instrument included in the assessment of effectiveness are recorded in the line item of the consolidated statements of earnings in which gain or loss on the hedged item is recorded. When assessing the effectiveness of the Company's fair value hedges, the Company excludes the changes in fair value related to the difference between the spot and the forward rate on its foreign currency forwards, the fair value not resulting from fluctuations in spot currency rates on the final notional exchange on cross currency swaps, and the time value of money of foreign exchange options and interest rate swaptions. For interest rate swaptions and cross-currency interest rate swaps designated under fair value hedges of interest rate risk, the change in the time value of money is recognized in other comprehensive income (loss) and amortized into earnings (net investment income) over its legal term.
As discussed in Note 4, from time to time the Company designates net investment hedges of its net investment in Aflac Japan. The Company makes its net investment hedge designation at the beginning of each quarter. For derivative hedging instruments designated as net investment hedges, Aflac follows the spot-rate method. According to that method, the change in fair value of the hedging instrument due to fluctuations in the spot exchange rate is recorded in the unrealized foreign currency component of other comprehensive income and reclassified to earnings only when the hedged net investment is sold, or when a liquidation of the respective net investment in the foreign entity is substantially completed. If and when a sale or liquidation occurs, the changes in fair value of the derivative deferred in the unrealized foreign currency component of other comprehensive income will be released in the same income statement line item where the gain (loss) on the hedged net investment would be recorded upon sale. All other changes in fair value of the hedging instrument are considered the “excluded component” and are accounted for in net investment gains (losses). Should these designated net investment hedge positions exceed the Company's net investment in Aflac Japan, the foreign exchange effect on the portion that exceeds its investment in Aflac Japan would be recognized in current earnings within net investment gains (losses).
The Company discontinues hedge accounting prospectively when (1) it is determined that the derivative is no longer highly effective in offsetting changes in the estimated cash flows or fair value of a hedged item; (2) the derivative is de-designated as a hedging instrument; or (3) the derivative expires or is sold, terminated or exercised.
When hedge accounting is discontinued on a cash flow hedge or fair value hedge, the derivative is carried in the consolidated balance sheets at its estimated fair value, with changes in estimated fair value recognized in current period earnings. For discontinued cash flow hedges, including those where the derivative is sold, terminated or exercised, amounts previously deferred in other comprehensive income (loss) are reclassified into earnings when earnings are impacted by the cash flow of the hedged item.
If a derivative is not designated as an accounting hedge or its use in managing risk does not qualify for hedge accounting, changes in the estimated fair value of the derivative are generally reported within other gains (losses), which is a component of net investment gains (losses). The fluctuations in estimated fair value of derivatives that have not been designated for hedge accounting can result in volatility in net earnings.
The Company receives and pledges cash or other securities as collateral on open derivative positions. Cash received as collateral is reported as an asset with a corresponding liability for the return of the collateral. Cash pledged as collateral is recorded as a reduction to cash, and a corresponding receivable is recognized for the return of the cash collateral. The Company generally can repledge or resell collateral obtained from counterparties, although the Company does not typically exercise such rights. Securities received as collateral are not recognized unless the Company was to exercise its right to sell that collateral or exercise remedies on that collateral upon a counterparty default. Securities that the Company has pledged as collateral continue to be carried as investment assets on its balance sheet.

Deferred Policy Acquisition Costs: Certain direct and incremental costs of acquiring insurance contracts are deferred and amortized with interest over the premium payment periods in proportion to the ratio of annual earned premium to total anticipated earned premium. Anticipated earned premium is estimated by using the same mortality, persistency and interest assumptions used in computing liabilities for future policy benefits. In this manner, the related acquisition expenses are matched with revenues. Deferred costs include the excess of current-year commissions over ultimate renewal-year commissions and certain incremental direct policy issue, underwriting and sales expenses. All of these incremental costs are directly related to successful policy acquisition.

For some products, policyholders can elect to modify product benefits, features, rights or coverages by exchanging a contract for a new contract or by amendment, endorsement, or rider to a contract, or by the election of a feature or coverage within a contract. These transactions are known as internal replacements. The Company performs a two-stage analysis of the internal replacements to determine if the modification is substantive to the base policy. The stages of evaluation are as follows: 1) determine if the modification is integrated with the base policy, and 2) if it is integrated, determine if the resulting contract is substantially changed.

For internal replacement transactions where the resulting contract is substantially unchanged, the policy is accounted for as a continuation of the replaced contract. Unamortized deferred acquisition costs from the original policy continue to be amortized over the expected life of the new policy, and the costs of replacing the policy are accounted for as policy maintenance costs and expensed as incurred. Examples include conversions of same age bands, certain family coverage changes, pricing era changes (decrease), ordinary life becomes reduced paid-up and certain reinstatements.

An internal replacement transaction that results in a policy that is substantially changed is accounted for as an extinguishment of the original policy and the issuance of a new policy. Unamortized deferred acquisition costs on the original policy are immediately expensed, and the costs of acquiring the new policy are capitalized and amortized in accordance with the Company's accounting policies for deferred acquisition costs.

Riders can be considered internal replacements that are either integrated or non-integrated resulting in either substantially changed or substantially unchanged treatment. Riders are evaluated based on the specific facts and circumstances of the rider and are considered an expansion of the existing benefits with additional premium required. Non-integrated riders to existing contracts do not change the Company's profit expectations for the related products and are treated as a new policy establishment for incremental coverage.

The Company measures the recoverability of DAC and the adequacy of its policy reserves annually by performing gross premium valuations on its business. (See the following discussion for further information regarding policy reserves.)

Goodwill: Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. The amount of goodwill recognized is also impacted by measurement differences resulting from certain assets and liabilities not recorded at fair value (e.g. income taxes, employee benefits). Goodwill is not amortized, but is tested for impairment at a level of a reporting unit at least annually, in the same reporting period each year. Goodwill is included in the line item “Other” assets in the consolidated balance sheets and was $268 million as of December 31, 2021, compared with $269 million at December 31, 2020. A significant majority of the goodwill balance is attributable to the following business combinations within the Aflac U.S. segment, which represents the reporting unit for goodwill impairment testing: (i) CAIC acquisition in 2009, (ii) Empoweredbenefits acquisition in 2015, (iii) Argus acquisition in 2019, and (iv) acquisition of Zurich's business in the fourth quarter of 2020.

Policy Liabilities: Future policy benefits represent insurance claims that are expected to occur in the future and are computed following a net level premium method using estimated future investment yields, persistency and recognized morbidity and mortality tables modified to reflect the Company's experience, including a provision for adverse deviation. These assumptions are generally established and considered locked at policy inception. These assumptions may only be unlocked in certain circumstances based on the results of periodic DAC recoverability and premium deficiency testing.
Unpaid policy claims are estimates computed primarily on an undiscounted basis using statistical analyses of historical claims experience adjusted for current trends and changed conditions. The ultimate liability may vary significantly from such estimates. The Company regularly adjusts these estimates as new claims experience emerges and reflects the changes in operating results in the year such adjustments are made.

Unearned premiums consist primarily of discounted advance premiums on deposit from policyholders in conjunction with their purchase of certain Aflac Japan limited-pay insurance products. These advanced premiums are deferred upon collection and recognized as earned premiums over the contractual premium payment period.

Other policyholders’ funds liability consists primarily of the fixed annuity line of business in Aflac Japan which has fixed benefits and premiums.

For internal replacements that are determined to be substantially changed, policy liabilities related to the original policy that was replaced are immediately released, and policy liabilities are established for the new insurance contract. Further, the policy reserves are evaluated based on the new policy features, and any change (up or down) necessary is recognized at the date of contract change/modification. Examples include conversions to higher age bands, certain family coverage changes, pricing era changes (increase), lapse & re-issue, certain reinstatements and certain other contract conversions. However, for internal replacements that are considered substantially unchanged, no changes to the reserves are recognized.

Reinsurance: The Company enters into reinsurance agreements with other companies in the normal course of business. For each reinsurance agreement, the Company determines if the agreement provides indemnification against loss or liability relating to insurance risk in accordance with applicable accounting standards. Reinsurance premiums and benefits paid or provided are accounted for on bases consistent with those used in accounting for the original policies issued and the terms of the reinsurance contracts. Premiums, benefits and DAC are reported net of insurance ceded.

Income Taxes: Income tax provisions are generally based on pretax earnings reported for financial statement purposes, which differ from those amounts used in preparing the Company's income tax returns. Deferred income taxes are recognized for temporary differences between the financial reporting basis and income tax basis of assets and liabilities, based on enacted tax laws and statutory tax rates applicable to the periods in which the Company expects the temporary differences to reverse. The Company records deferred tax assets for tax positions taken based on its assessment of whether the tax position is more likely than not to be sustained upon examination by taxing authorities. A valuation allowance is established for deferred tax assets when it is more likely than not that an amount will not be realized.

Policyholder Protection Corporation and State Guaranty Association Assessments: In Japan, the government has required the insurance industry to contribute to a policyholder protection corporation. The Company recognizes a charge for its estimated share of the industry's obligation once it is determinable. The Company reviews the estimated liability for policyholder protection corporation contributions on an annual basis and reports any adjustments in Aflac Japan's expenses.

In the U.S., each state has a guaranty association that supports insolvent insurers operating in those states. The Company's policy is to accrue assessments when the entity for which the insolvency relates has met its state of domicile's statutory definition of insolvency, the amount of the loss is reasonably estimable and the related premium upon which the assessment is based is written. See Note 15 of the Notes to the Consolidated Financial Statements for further discussion of the guaranty fund assessments charged to the Company.

Treasury Stock: Treasury stock is reflected as a reduction of shareholders' equity at cost. The Company uses the weighted-average purchase cost to determine the cost of treasury stock that is reissued. The Company includes any gains and losses in additional paid-in capital when treasury stock is reissued.

Share-Based Compensation: The Company measures compensation cost related to its share-based payment transactions at fair value on the grant date, and the Company recognizes those costs in the financial statements over the vesting period during which the employee provides service in exchange for the award. The Company has made an entity-wide accounting policy election to estimate the number of awards that are expected to vest and the corresponding forfeitures.

Earnings Per Share: The Company computes basic earnings per share (EPS) by dividing net earnings by the weighted-average number of unrestricted shares outstanding for the period. Diluted EPS is computed by dividing net earnings by the weighted-average number of shares outstanding for the period plus the shares representing the dilutive effect of share-based awards.
Reclassifications: Certain reclassifications have been made to prior-year amounts to conform to current-year reporting classifications. These reclassifications had no impact on net earnings or total shareholders' equity.

New Accounting Pronouncements

Recently Adopted Accounting Pronouncements

ASU 2020-04 Reference Rate Reform: Facilitation of the Effects of Reference Rate Reform on Financial Reporting, as clarified and amended by:
ASU 2021-01 Reference Rate Reform: Relief Extended to Derivatives Impacted by Discounting Transition

In March 2020, the FASB issued amendments that provide optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships, and other transactions affected by the reference rate reform if certain criteria are met. The amendments in this ASU only apply to contracts, hedging relationships, and other transactions that reference the London Interbank Offered Rate (LIBOR) or another reference rate expected to be discontinued because of reference rate reform.

An entity may elect to apply the amendments as of any date from the beginning of an interim period that includes or is subsequent to March 12, 2020, or prospectively from a date within an interim period that includes or is subsequent to March 12, 2020, up to the date that the financial statements are available to be issued.

The amendments generally expire on December 31 2022, i.e., they do not apply to contract modifications made after December 31, 2022, new hedging relationships entered into after December 31, 2022, and hedging relationships evaluated for periods after December 31, 2022.

In January 2021, the FASB issued a standard to permit entities to apply optional expedients in ASC 848 to derivative instruments modified because of discounting transition. Discounting transition refers to the changing of interest rates used for margining, discounting, or contract price alignment of derivative instruments to transition to alternative rates.The amendment is effective immediately.

This standard was adopted on April 1, 2020. The adoption of the new guidance did not have an impact on the Company’s financial statements. The Company will continue to evaluate the impacts of reference rate reform on contract modifications and hedging relationships through December 31, 2022.

ASU 2019-04 Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments

In April 2019, the FASB issued Codification improvements to clarify and correct certain areas of guidance amended as part of ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities; ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments; and ASU 2017-12, Derivative and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities.

The most significant of these improvements to the Company was related to the Codification improvement to ASU 2017-12 and the clarification that a one-time reclassification of assets that are eligible to be hedged under the last-of-layer method (i.e., certain pre-payable securities) from held-to-maturity to available-for-sale is allowed under the new hedge accounting guidance and would not impact the Company’s ability to continue to classify other bonds as held-to-maturity.

The other amendments related to ASU 2017-12 and 2016-01 are either not significant, or were previously implemented as part of the related ASU adoptions.

Applicable amendments related to ASU 2016-13 are discussed within the recent adoption of that update below.

This standard was adopted on January 1, 2020. The adoption of this guidance resulted in a reclassification of $6.9 billion (at amortized cost) of pre-payable fixed-maturity securities from the held-to-maturity to the available-for-sale category. The reclassification resulted in recording in beginning 2020 accumulated other comprehensive income a net unrealized gain of $848 million on an after-tax basis, based on the securities’ fair values on the reclassification date. The reclassification impacted the adoption of ASU 2016-13 (see ASU 2016-13 below for additional details).
ASU 2016-02 Leases, as clarified and amended by:
ASU 2018-01, Leases: Land Easement Practical Expedient for Transition to Topic 842
ASU 2018-10, Codification Improvements to Topic 842, Leases
ASU 2018-11, Leases, Targeted Improvements
ASU 2018-20, Leases: Narrow-Scope Improvements for Lessors

In February 2016, the FASB issued updated guidance for accounting for leases (“Leases Update”). Per the Leases Update, lessees are required to recognize all leases on the balance sheet with the exception of short-term leases. A lease liability will be recorded for the obligation of a lessee to make lease payments arising from a lease. Leases will be classified as finance or operating, with classification affecting the pattern and classification of expense recognition in the income statement. The Leases Update provided a number of optional practical expedients. The Company elected the "package of practical expedients," which permits the Company not to reassess under the new standard its prior conclusions about lease identification, lease classification and initial direct costs. Under the Leases Update, lessor accounting is unchanged.

This standard was adopted on January 1, 2019. The Company has operating and finance leases for office space and equipment. The Company elected the short-term lease exemption for all classes of leases which allows the Company to not recognize right-of-use assets and lease liabilities on the consolidated balance sheet and allows the Company to recognize the lease expense for short-term leases on a straight-line basis over the lease term. The Company elected the practical expedient to not separate lease and non-lease components and applied it to all classes of leases where the non-lease components are not significant. Some of the Company's leases include options to extend or terminate the lease and the lease terms may include such options when it is reasonably certain that the Company will exercise that option. Certain leases also include options to purchase the leased property. The leases within scope of the leases update increased the Company's right-of-use assets and lease liabilities recorded in its beginning 2019 consolidated balance sheet by $134 million.

As of January 1, 2019, the Company did not have land easements, but has elected the practical expedient as a safe harbor.

The Company elected the optional transition method and as a safe harbor, the practical expedient provided to lessors.

The Company has made an accounting policy election to exclude amounts collected from customers for all sales (and other similar) taxes from the transaction price. The adoption of the Leases Update and related amendments did not have a significant impact on the Company's financial position, results of operations, or disclosures.

ASU 2016-13 Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments, as clarified and amended by:
ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815,             Derivatives and Hedging, and Topic 825, Financial Instruments
ASU 2019-05, Financial Instruments - Credit Losses (Topic 326), Targeted Transition Relief
ASU 2019-11, Codification Improvements to Topic 326, Financial Instruments - Credit Losses

In June 2016, the FASB issued amendments that require a financial asset (or a group of financial assets) measured at amortized cost to be presented net of an allowance for credit losses (Credit Losses ASU) in order to reflect the amount expected to be collected on the financial asset(s). The measurement of expected credit losses is amended by replacing the incurred loss impairment methodology with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information. Credit losses on available-for-sale debt securities is measured in a manner similar to prior U.S. GAAP; however, the amendments require that credit losses be presented as an allowance rather than as a write-down. Other amendments include changes to the balance sheet presentation and interest income recognition of purchased financial assets with a more-than-insignificant credit deterioration since origination (PCD financial assets).

This standard was adopted on January 1, 2020. The Company recorded a cumulative effect adjustment with a decrease to beginning 2020 retained earnings of $56 million, net of taxes. See Note 3 of the Notes to the Consolidated Financial Statements for credit loss disclosures. The following line items in the consolidated balance sheets were most significantly impacted by the adoption of the new accounting standard:

•Fixed maturity securities held to maturity, at amortized cost
•Commercial mortgage and other loans
•Reinsurance recoverable, included within Other asset
Accounting Pronouncements Pending Adoption

ASU 2018-12 Financial Services - Insurance: Targeted Improvements to the Accounting for Long-Duration
Contracts, as clarified and amended by:
ASU 2019-09 Financial Services - Insurance: Effective Date
ASU 2020-11 Financial Services - Insurance: Effective Date and Early Application

In August 2018, the FASB issued amendments that will significantly change how insurers account for long-duration contracts. The amendments will change existing recognition, measurement, presentation, and disclosure requirements. Issues addressed in the new guidance include: 1) a requirement to review and, if there is a change, update assumptions for the liability for future policy benefits at least annually, and to update the discount rate assumption quarterly, 2) accounting for market risk benefits at fair value, 3) simplified amortization for deferred acquisition costs, and 4) enhanced financial statement presentation and disclosures.

In November 2019, the FASB issued an amendment extending the effective date for public business entities that meet the definition of an SEC filer, excluding entities eligible to be small reporting companies as defined by the SEC, by one year. In November 2020, the FASB issued an amendment providing an additional year deferral for all insurance entities due to the impact of COVID-19. The amendments are now effective for the Company for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2022. Early application of the amendments is permitted.

The Company continues to evaluate the impact of adoption and expects that the adoption will have a significant impact on the Company’s financial position, results of operations, and disclosures. The Company anticipates that the requirement to update assumptions for liability for future policy benefits (LFPB) will have a significant impact on its results of operations, systems, processes and controls and that the requirement to update discount rates will have a significant impact on its equity.

As part of working toward implementation of the updated standard, the Company has made progress on key accounting policy decisions, including processes to identify insurance policy groupings (cohorts) for LFPB measurement and DAC amortization purposes, applicable discount rates, development of liability cash flow and claim expense assumptions, and DAC amortization methodology.

The Company will not early adopt the updated standard and has selected the modified retrospective transition method. Based upon this transition method, the Company currently estimates that the January 1, 2021 transition date (Transition Date) impact from adoption is likely to result in a decrease in accumulated other comprehensive income (AOCI) in a range between $18 billion and $20 billion. This is due to updating the LFPB discount rate assumptions from the rates locked in for reserves held as of the Transition Date to rates determined by reference to the Transition Date market level yields for upper-medium-grade (low credit risk) fixed income instruments (as of December 31, 2020). The variability around the impact of adoption results from the Company making certain estimates, primarily related to the determination of Transition Date market level yields.

The Company has advanced and continues to refine the design of its discount rate methodology for both the U.S. and Japan insurance business. The methodology incorporates constructing a discount rate curve separately for discounting cash flows used to calculate the U.S. and Japan LFPB, with each curve intended to be reflective of the currency, tenor and characteristics of the insurance liabilities. Discount rates comprising each curve will be determined by reference to upper-medium grade (low credit risk) fixed-income instrument yields that are intended to reflect the duration characteristics of the corresponding insurance liabilities. The Company intends to use for these yields single-A rated fixed income instruments with credit ratings based on international rating standards. Where only local ratings are available, the Company intends to select the fixed-income instruments with local ratings that are equivalent to a single-A rating based on international rating standards. The methodology will be designed to prioritize observable inputs based on market data available in the local debt markets where the respective policies were issued in the currency in which the policies are denominated. For the discount rates applicable to tenors for which the single-A debt market is not liquid or there is little or no observable market data, the Company will use various estimation techniques consistent with the fair value guidance in ASC 820, which include, but are not limited to: (i) for tenors where there is less observable market data and/or the observable market data is available for similar instruments, estimating tenor-specific single-A credit spreads and applying them to risk-free government rates; (ii) for tenors where there is very limited or no observable single-A or similar market data, interpolation and extrapolation techniques. Discount rates will be updated each reporting period.

Long duration insurance contracts issued by the Company will be grouped into annual calendar-year cohorts based on the contract issue date, reportable segment, legal entity and product type. Limited pay contracts will be grouped into separate
cohorts from other traditional products in the same manner and will be further separated based on their premium payment structures. Riders will be combined with base policies with similar insurance coverage types and the same contract issue years.

In addition to the preliminary policy elections related to cohorts and LFPB discount rates directly impacting Transition Date AOCI, the Company has also advanced the following accounting policies relevant to the post-Transition Date accounting:

•Cash flow assumptions underlying insurance liabilities will be evaluated as to whether an update is needed at least annually in the same fiscal quarter each year. To facilitate the review, experience studies will be performed annually in the consistent quarter year-to-year to substantiate assumptions, including mortality, morbidity, and terminations in future periods.
•Locked-in discount rates used for the computation of interest accretion on LFPB for policies issued on or after January 1, 2021 will be determined for each issue-year cohort as a single discount rate, calculated as the weighted-average of monthly upper-medium grade (low-credit risk) fixed-income instrument forward curves over the calendar year, determined using the methodology described above and weighted using issued annualized premiums for each issue month. The single discount rate for each issue-year cohort will remain unchanged after the calendar year of issue. Locked-in discount rates on the policies held at Transition Date reflect the locked-in rates in existence immediately before the Transition Date.
•For DAC amortization, the Company has made a preliminary election to group insurance policies into cohorts that are consistent with the groupings used in estimating the associated LFPB. DAC will be amortized on a constant level basis for the grouped contracts over the expected remaining term of the related contracts. For both life and health products issued by Aflac Japan, the constant-level basis used will be units in force, which is a proxy for face amount and insurance in force, respectively. For life products issued by Aflac U.S., the constant level basis used will be face amount of policies in force; for health products issued by Aflac U.S., the constant level basis used will be the number of policies in force.
•The Company has made a preliminary entity-wide election to use locked-in claim expense assumptions determined for each issue-year cohort as a percentage of incurred claims; these assumptions would remain unchanged over the term of the insurance policy.

The Company has created a governance framework and a plan to support implementation of the updated standard. As part of its implementation plan, the Company has also advanced the modernization of its actuarial technology platform to enhance its modeling, data management, experience study and analytical capabilities, increase the end-to-end automation of key reporting and analytical processes and optimize its control framework. The Company has also put in place internal controls related to the new processes created as part of implementing the updated standard and will continue to refine and maturate these internal controls until the formal implementation in the first quarter of 2023.

The Company has recently begun testing its reporting and disclosure capabilities under the new ASU for post-Transition Date accounting periods.

The Company currently has no products with market risk benefits.
Recent accounting guidance not discussed above is not applicable, did not have, or is not expected to have a material impact to the Company's business.
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BUSINESS SEGMENT AND FOREIGN INFORMATION
 12 Months Ended
Dec. 31, 2021
Segment Reporting [Abstract]  
BUSINESS SEGMENT INFORMATION BUSINESS SEGMENT AND FOREIGN INFORMATION
The Company consists of two reportable insurance business segments: Aflac Japan and Aflac U.S., both of which sell supplemental health and life insurance. In addition, the Parent Company, other operating business units that are not individually reportable and business activities, including reinsurance retrocession activities, not included in Aflac Japan or Aflac U.S. are included in Corporate and other.

The Company does not allocate corporate overhead expenses to business segments. Consistent with U.S. GAAP accounting guidance for segment reporting, the Company evaluates and manages its business segments using a financial performance measure called pretax adjusted earnings. Adjusted earnings are adjusted revenues less benefits and adjusted expenses. The adjustments to both revenues and expenses account for certain items that cannot be predicted or that are outside management’s control. Adjusted revenues are U.S. GAAP total revenues excluding net investment gains and losses, except for amortized hedge costs/income related to foreign currency exposure management strategies and net interest cash flows from derivatives associated with certain investment strategies. Adjusted expenses are U.S. GAAP total acquisition and operating expenses including the impact of interest cash flows from derivatives associated with notes payable but excluding any nonrecurring or other items not associated with the normal course of the Company’s insurance
operations and that do not reflect the Company’s underlying business performance. The Company excludes income taxes related to operations to arrive at pretax adjusted earnings. Information regarding operations by reportable segment and Corporate and other for the years ended December 31 follows:
(In millions)202120202019
Revenues:
Aflac Japan:
   Net earned premiums:
             Cancer$5,829 $6,119 $6,031 
             Medical and other health3,400 3,596 3,582 
             Life insurance2,624 2,955 3,159 
   Adjusted net investment income (1),(2)
3,031 2,659 2,496 
   Other income41 42 45 
               Total adjusted revenue Aflac Japan14,925 15,371 15,313 
Aflac U.S.:
   Net earned premiums:
             Accident/disability2,524 2,614 2,665 
             Cancer1,216 1,275 1,309 
             Other health1,542 1,571 1,548 
             Life insurance332 298 286 
   Adjusted net investment income (3)
754 705 720 
   Other income121 102 22 
           Total adjusted revenue Aflac U.S.6,489 6,565 6,550 
Corporate and other (4), (5)
175 384 393 
           Total adjusted revenues21,589 22,320 22,256 
Net investment gains (losses) (1),(2),(3),(4)
517 (173)51 
           Total revenues$22,106 $22,147 $22,307 
(1) Amortized hedge costs of $76, $206 and $257 in 2021, 2020 and 2019, respectively, related to certain foreign currency exposure management strategies have been reclassified from net investment gains (losses) and reported as a deduction from net investment income when analyzing operations.
(2) Net interest cash flows from derivatives associated with certain investment strategies of $(33), $9, and $(17) in 2021, 2020, and 2019, respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income when analyzing operations.
(3) Net interest cash flows from derivatives associated with certain investment strategies of $2 and $3 in 2021 and 2020, respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income when analyzing operations.
(4) Amortized hedge income of $57, $97 and $89 in 2021, 2020 and 2019, respectively, related to certain foreign currency exposure management strategies has been reclassified from net investment gains (losses) and reported as an increase to net investment income when analyzing operations.
(5) The change in value of federal historic rehabilitation and solar investments in partnerships of $138 in 2021 is included as a reduction to net investment income. Tax credits on these investments of $115 in 2021 has been recorded as an income tax benefit in the consolidated statement of earnings. See Note 3 of the Notes to the Consolidated Financial Statements for additional information on these investments.
(In millions)202120202019
Pretax earnings:
Aflac Japan (1),(2)
$3,754 $3,263 $3,261 
Aflac U.S. (3)
1,478 1,268 1,272 
Corporate and other (4),(5),(6)
(298)(115)(72)
    Pretax adjusted earnings (7)
4,934 4,416 4,461 
Net investment gains (losses) (1),(2),(3),(4),(5)
462 (229)(15)
Other income (loss) (74)

(28)(1)

    Total earnings before income taxes$5,322 $4,159 $4,445 
Income taxes applicable to pretax adjusted earnings$915 $864 $1,147 
Effect of foreign currency translation on after-tax
  adjusted earnings		(38)31 15 
(1) Amortized hedge costs of $76, $206 and $257 in 2021, 2020 and 2019, respectively, related to certain foreign currency exposure management strategies have been reclassified from net investment gains (losses) and reported as a deduction from net investment income when analyzing operations.
(2) Net interest cash flows from derivatives associated with certain investment strategies of $(33), $9, and $(17) in 2021, 2020, and 2019, respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income when analyzing operations.
(3) Net interest cash flows from derivatives associated with certain investment strategies of $2 and $3 in 2021 and 2020, respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income when analyzing operations.
(4) Amortized hedge income of $57, $97 and $89 in 2021, 2020 and 2019, respectively, related to certain foreign currency exposure management strategies has been reclassified from net investment gains (losses) and reported as an increase to net investment income when analyzing operations.
(5) A gain of $55, $56 and $66 in 2021, 2020 and 2019, respectively, related to the interest rate component of the change in fair value of foreign currency swaps on notes payable has been reclassified from net investment gains (losses) and included in adjusted earnings when analyzing operations.
(6) The change in value of federal historic rehabilitation and solar investments in partnerships of $138 in 2021 is included as a reduction to net investment income. Tax credits on these investments of $115 in 2021 has been recorded as an income tax benefit in the consolidated statement of earnings. See Note 3 of the Notes to the Consolidated Financial Statements for additional information on these investments.
(7) Includes $170, $167 and $135 of interest expense on debt in 2021, 2020 and 2019, respectively.

Assets as of December 31 were as follows:
(In millions)20212020
Assets:
Aflac Japan$128,536 $137,271 
Aflac U.S.23,106 22,864 
Corporate and other5,900 4,951 
    Total assets$157,542 $165,086 

Yen-Translation Effects: The following table shows the yen/dollar exchange rates used for or during the periods ended December 31. Exchange effects were calculated using the same yen/dollar exchange rate for the current year as for each respective prior year.
202120202019
Statements of Earnings:
Weighted-average yen/dollar exchange rate (1)
109.79 106.86 109.07 
Yen percent strengthening (weakening)(2.7)%2.1 %1.2 %
Exchange effect on pretax adjusted earnings (in millions)$(47)$38 $20 
20212020
Balance Sheets:
Yen/dollar exchange rate at December 31(1)
115.02 103.50 
Yen percent strengthening (weakening)(10.0)%5.9 %
Exchange effect on total assets (in millions)$(9,635)$7,970 
Exchange effect on total liabilities (in millions)(7,566)7,870 
(1) Rates are based on the published MUFG Bank, Ltd. telegraphic transfer middle rate (TTM)

Transfers of funds from Aflac Japan: Aflac Japan makes payments to the Parent Company for management fees, allocated expenses and remittances of earnings. Information on transfers for each of the years ended December 31 is shown below. See Note 13 for information concerning restrictions on transfers from Aflac Japan.
(In millions)202120202019
Management fees$59 $71 $75 
Allocated expenses0 0 4 
Profit remittances2,138 1,215 2,070 
Total transfers from Aflac Japan$2,197 $1,286 $2,149 

Property and Equipment: The costs of buildings, furniture and equipment are depreciated principally on a straight-line basis over their estimated useful lives (maximum of 50 years for buildings and 20 years for furniture and equipment). Expenditures for maintenance and repairs are expensed as incurred; expenditures for betterments are capitalized and depreciated. Classes of property and equipment as of December 31 were as follows:
(In millions)20212020
Property and equipment:
Land$168 $168 
Buildings491 523 
Equipment and furniture542 566 
Total property and equipment1,201 1,257 
Less accumulated depreciation663 656 
Net property and equipment$538 $601 

Receivables: Receivables consist primarily of monthly insurance premiums due from individual policyholders or their employers for payroll deduction of premiums, net of current expected credit losses. At December 31, 2021, $195 million, or 28.1% of total receivables, were related to Aflac Japan's operations, compared with $201 million, or 25.2%, at December 31, 2020.
v3.22.0.1
INVESTMENTS
 12 Months Ended
Dec. 31, 2021
Investments [Abstract]  
Investments INVESTMENTS
Net Investment Income

The components of net investment income for the years ended December 31 were as follows:
(In millions)202120202019
Fixed maturity securities$3,068 $3,113 $3,141 
Equity securities35 29 37 
Commercial mortgage and other loans570 545 468 
Other investments (1)
356 145 53 
Short-term investments and cash equivalents7 18 56 
Gross investment income4,036 3,850 3,755 
Less investment expenses218 212 177 
Net investment income$3,818 $3,638 $3,578 
(1) The change in value of federal historic rehabilitation and solar investments in partnerships of $138 in 2021 is included as a reduction to net investment income. Tax credits on these investments of $115 in 2021 have been recorded as an income tax benefit in the consolidated statement of earnings.
Investment Holdings
The amortized cost for the Company's investments in fixed maturity securities, the cost for equity securities and the fair values of these investments at December 31 are shown in the following tables.
  2021
(In millions)
Amortized
Cost		Allowance for Credit LossesGross
Unrealized
Gains		Gross
Unrealized
Losses		  Fair
  Value
Securities available for sale, carried at fair
  value through other comprehensive income:
Fixed maturity securities:
  Yen-denominated:
Japan government and agencies$30,335 $0 $3,343 $61 $33,617 
Municipalities1,192 0 322 5 1,509 
Mortgage- and asset-backed securities300 0 19 1 318 
Public utilities4,462 0 906 2 5,366 
Sovereign and supranational760 0 82 0 842 
Banks/financial institutions6,963 0 787 72 7,678 
Other corporate7,148 0 1,535 26 8,657 
Total yen-denominated51,160 0 6,994 167 57,987 
  U.S. dollar-denominated:
U.S. government and agencies196 0 8 1 203 
Municipalities1,340 0 189 2 1,527 
Mortgage- and asset-backed securities897 0 33 2 928 
Public utilities3,781 0 909 5 4,685 
Sovereign and supranational222 0 57 6 273 
Banks/financial institutions3,169 0 747 3 3,913 
Other corporate24,604 0 4,629 53 29,180 
Total U.S. dollar-denominated34,209 0 6,572 72 40,709 
Total securities available for sale$85,369 $0 $13,566 $239 $98,696 
 
2020
(In millions)Amortized
Cost		Allowance for Credit LossesGross
Unrealized
Gains		Gross
Unrealized
Losses		Fair
  Value
Securities available for sale, carried at fair value
  through other comprehensive income:
Fixed maturity securities:
  Yen-denominated:
Japan government and agencies$32,959 $0 $4,182 $52 $37,089 
Municipalities1,324 0 374 5 1,693 
Mortgage- and asset-backed securities342 0 27 1 368 
Public utilities4,777 0 1,096 1 5,872 
Sovereign and supranational981 0 108 0 1,089 
Banks/financial institutions7,552 0 886 102 8,336 
Other corporate8,114 0 1,747 37 9,824 
Total yen-denominated56,049 0 8,420 198 64,271 
  U.S. dollar-denominated:
U.S. government and agencies245 0 16 0 261 
Municipalities1,154 0 173 2 1,325 
Mortgage- and asset-backed securities667 0 8 5 670 
Public utilities4,013 0 947 15 4,945 
Sovereign and supranational232 0 64 3 293 
Banks/financial institutions2,973 0 758 7 3,724 
Other corporate26,297 38 4,385 251 30,393 
Total U.S. dollar-denominated35,581 38 6,351 283 41,611 
Total securities available for sale$91,630 $38 $14,771 $481 $105,882 

  2021
(In millions)
Amortized
Cost		Allowance for Credit LossesNet Carrying AmountGross
Unrealized
Gains		Gross
Unrealized
Losses		Fair  
Value  
Securities held to maturity, carried at
  amortized cost:
Fixed maturity securities:
  Yen-denominated:
Japan government and agencies$21,089 $3 $21,086 $4,613 $0 $25,699 
Municipalities335 0 335 101 0 436 
Public utilities44 1 43 12 0 55 
Sovereign and supranational518 4 514 136 0 650 
Other corporate22 0 22 7 0 29 
Total yen-denominated22,008 8 22,000 4,869 0 26,869 
Total securities held to maturity$22,008 $8 22,000 $4,869 $0 $26,869 
  2020
(In millions)Amortized
Cost		Allowance for Credit LossesNet Carrying AmountGross
Unrealized
Gains		Gross
Unrealized
Losses		Fair  
Value
Securities held to maturity, carried at
  amortized cost:
Fixed maturity securities:
  Yen-denominated:
Japan government and agencies$23,448 $3 $23,445 $5,625 $0 $29,070 
Municipalities377 0 377 122 0 499 
Public utilities48 1 47 14 0 61 
Sovereign and supranational577 6 571 165 0 736 
Other corporate24 0 24 9 0 33 
Total yen-denominated24,474 10 24,464 5,935 0 30,399 
Total securities held to maturity$24,474 $10 $24,464 $5,935 $0 $30,399 

  
20212020
(In millions)Fair ValueFair Value
Equity securities, carried at fair value through net earnings:
Equity securities:
      Yen-denominated$744 $680 
      U.S. dollar-denominated817 603 
      Other currencies42 0 
Total equity securities$1,603 $1,283 

The methods of determining the fair values of the Company's investments in fixed maturity securities and equity securities are described in Note 5.

During 2021 and 2019, the Company did not reclassify any investments from the held-to-maturity category to the available-for-sale category. During 2020, as a result of the adoption of ASU 2019-04 discussed in Note 1, the Company reclassified $6.9 billion (at amortized cost) of pre-payable fixed-maturity securities from the held-to-maturity category to the available-for-sale category. This reclassification resulted in recording in accumulated other comprehensive income a net unrealized gain of $848 million on an after-tax basis.
Contractual and Economic Maturities
The contractual and economic maturities of the Company's investments in fixed maturity securities at December 31, 2021, were as follows:
(In millions)
Amortized
Cost (1)
Fair
Value
Available for sale:
Due in one year or less$984 $1,015 
Due after one year through five years8,145 8,782 
Due after five years through 10 years13,288 15,491 
Due after 10 years61,755 72,163 
Mortgage- and asset-backed securities1,197 1,245 
Total fixed maturity securities available for sale$85,369 $98,696 
Held to maturity:
Due in one year or less$0 $0 
Due after one year through five years44 48 
Due after five years through 10 years10,121 11,772 
Due after 10 years11,835 15,049 
Mortgage- and asset-backed securities0 0 
Total fixed maturity securities held to maturity$22,000 $26,869 
(1) Net of allowance for credit losses

Economic maturities are used for certain debt instruments with no stated maturity where the expected maturity date is based on the combination of features in the financial instrument such as the right to call or prepay obligations or changes in coupon rates.
Investment Concentrations

The Company's process for investing in credit-related investments begins with an independent approach to underwriting each issuer's fundamental credit quality. The Company evaluates independently those factors that it believes could influence an issuer's ability to make payments under the contractual terms of the Company's instruments. This includes a thorough analysis of a variety of items including the issuer's country of domicile (including political, legal, and financial considerations); the industry in which the issuer competes (with an analysis of industry structure, end-market dynamics, and regulation); company specific issues (such as management, assets, earnings, cash generation, and capital needs); and contractual provisions of the instrument (such as financial covenants and position in the capital structure). The Company further evaluates the investment considering broad business and portfolio management objectives, including asset/liability needs, portfolio diversification, and expected income.

Investment exposures that individually exceeded 10% of shareholders' equity as of December 31 were as follows:
20212020
(In millions)Credit
Rating		Amortized
Cost		Fair
Value		Credit
Rating		Amortized
Cost		Fair
Value
Japan National Government(1)
A+$50,186$57,862A+$55,153$64,657
(1)Japan Government Bonds (JGBs) or JGB-backed securities
Net Investment Gains and Losses

Information regarding pretax net gains and losses from investments for the years ended December 31 follows:
(In millions)202120202019
Net investment gains (losses):
Sales and redemptions:
Fixed maturity securities available for sale:
Gross gains from sales$64 $31 $115 
Gross losses from sales(52)(47)(68)
Foreign currency gains (losses) on sales and redemptions1 (69)(16)
Total sales and redemptions13 (85)31 
Equity securities164 184 

101 
Loan loss reserves (1)
0 0 (18)
Credit losses:
Fixed maturity securities available for sale 38 (38)0 
Fixed maturity securities held to maturity1 1 0 
Commercial mortgage and other loans6 (93)0 
Impairment losses (2)
(20)(49)(13)
Loan commitments4 (21)0 
Reinsurance recoverables and other(2)0 0 
Total credit losses27 (200)(13)
Derivatives and other:
Derivative gains (losses)(805)399 (174)
Foreign currency gains (losses)1,069 (568)(62)
Total derivatives and other264 (169)(236)
Total net investment gains (losses)$468 $(270)$(135)
(1) U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only
(2) Includes OTTI losses in 2019

The unrealized holding gains, net of losses, recorded as a component of net investment gains and losses for the year ended December 31, 2021, that relate to equity securities still held at the December 31, 2021, reporting date was $141 million.
Unrealized Investment Gains and Losses

Information regarding changes in unrealized gains and losses from investments recorded in AOCI for the years ended December 31 follows:
(In millions)202120202019
Changes in unrealized gains (losses):
Fixed maturity securities, available for sale$(960)$2,399 $5,852 
Total change in unrealized gains (losses)$(960)$2,399 $5,852 

Effect on Shareholders' Equity

The net effect on shareholders' equity of unrealized gains and losses from fixed maturity securities at December 31 was as follows:
(In millions)20212020
Unrealized gains (losses) on securities available for sale$13,330 $14,290 
Deferred income taxes(3,728)(3,929)
Shareholders’ equity, unrealized gains (losses) on fixed maturity securities$9,602 $10,361 
Gross Unrealized Loss Aging

The following tables show the fair values and gross unrealized losses of the Company's available-for-sale investments, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at December 31.
 
  2021
  TotalLess than 12 months12 months or longer
(In millions)Fair
Value		Unrealized
Losses		Fair
Value		Unrealized
Losses		Fair
Value		Unrealized
Losses
Fixed maturity securities available
   for sale:
  U.S. government and
      agencies:
  U.S. dollar-denominated$1 $1 $0 $1 $1 $0 
  Japan government and
      agencies:
  Yen-denominated2,868 61 445 3 2,423 58 
  Municipalities:
  U.S. dollar-denominated82 2 79 2 3 0 
  Yen-denominated187 5 53 0 134 5 
Mortgage- and asset-
    backed securities:
  U.S. dollar-denominated278 2 278 2 0 0 
  Yen-denominated33 1 0 0 33 1 
  Public utilities:
  U.S. dollar-denominated130 5 70 2 60 3 
  Yen-denominated26 2 0 0 26 2 
  Sovereign and supranational:
  U.S. dollar-denominated37 6 6 1 31 5 
  Banks/financial institutions:
  U.S. dollar-denominated292 3 274 3 18 0 
  Yen-denominated2,074 72 1,011 16 1,063 56 
  Other corporate:
  U.S. dollar-denominated1,365 53 458 8 907 45 
  Yen-denominated 541 26 274 4 267 22 
  Total$7,914 $239 $2,948 $42 $4,966 $197 
  2020
  TotalLess than 12 months12 months or longer
(In millions)Fair
Value		Unrealized
Losses		Fair
Value		Unrealized
Losses		Fair
Value		Unrealized
Losses
Fixed maturity securities available
   for sale:
  Japan government and
      agencies:
  Yen-denominated$2,604 $52 $2,604 $52 $0 $0 
  Municipalities:
  U.S. dollar-denominated94 2 94 2 0 0 
  Yen-denominated183 5 169 4 14 1 
Mortgage- and asset-
    backed securities:
  U.S. dollar-denominated360 5 360 5 0 0 
  Yen-denominated37 1 37 1 0 0 
  Public utilities:
  U.S. dollar-denominated326 15 208 7 118 8 
  Yen-denominated135 1 135 1 0 0 
  Sovereign and supranational:
U.S. dollar-denominated39 3 39 3 0 0 
  Banks/financial institutions:
  U.S. dollar-denominated82 7 44 1 38 6 
  Yen-denominated1,809 102 765 36 1,044 66 
  Other corporate:
  U.S. dollar-denominated4,499 251 2,157 59 2,342 192 
  Yen-denominated613 37 290 13 323 24 
  Total $10,781 $481 $6,902 $184 $3,879 $297 

Analysis of Securities in Unrealized Loss Positions

The unrealized losses on the Company's fixed maturity securities investments have been primarily related to general market changes in interest rates, foreign exchange rates, and/or the levels of credit spreads rather than specific concerns with the issuer's ability to pay interest and repay principal.

For any significant declines in fair value of its fixed maturity securities, the Company performs a more focused review of the related issuers' credit profile. For corporate issuers, the Company evaluates their assets, business profile including industry dynamics and competitive positioning, financial statements and other available financial data. For non-corporate issuers, the Company analyzes all sources of credit support, including issuer-specific factors. The Company utilizes information available in the public domain and, for certain private placement issuers, from consultations with the issuers directly. The Company also considers ratings from Nationally Recognized Statistical Rating Organizations (NRSROs), as well as the specific characteristics of the security it owns including seniority in the issuer's capital structure, covenant protections, or other relevant features. From these reviews, the Company evaluates the issuers' continued ability to service the Company's investment through payment of interest and principal.

Assuming no credit-related factors develop, unrealized gains and losses on fixed maturity securities are expected to diminish as investments near maturity. Based on its credit analysis, the Company believes that the issuers of its fixed maturity investments in the sectors shown in the table above have the ability to service their obligations to the Company, and the Company does not intend to sell the investments and it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost bases, which may be at maturity.

However, from time to time the Company identifies certain available-for-sale fixed maturity securities where the amortized cost basis exceeds the present value of the cash flows expected to be collected due to credit related factors and as a
result, a credit allowance will be estimated. Refer to the Allowance for Credit Losses section below for additional information.

Commercial Mortgage and Other Loans

The Company classifies its TREs, CMLs and MMLs as held-for-investment and includes them in the commercial mortgage and other loans line on the consolidated balance sheets. The Company carries them on the balance sheet at amortized cost less an estimated allowance for credit losses.

The table below reflects the composition of the carrying value for commercial mortgage and other loans by property type as of December 31.
(In millions)20212020
Amortized Cost% of TotalAmortized Cost% of Total
Commercial Mortgage and other loans
  Transitional real estate loans:
    Office$2,001 16.7 $2,115 19.7 
    Retail267 2.2 125 1.2 
    Apartments/Multi-Family1,893 15.8 1,782 16.6 
    Industrial94 .8 85 .8 
    Hospitality876 7.3 1,106 10.3 
    Other228 1.9 81 .7 
        Total transitional real estate loans5,359 44.7 5,294 49.3 
Commercial mortgage loans:
     Office398 3.3 401 3.7 
     Retail332 2.8 340 3.2 
     Apartments/Multi-Family649 5.4 588 5.5 
     Industrial525 4.4 391 3.6 
        Total commercial mortgage loans1,904 15.9 1,720 16.0 
Middle market loans4,697 39.4 3,720 34.7 
        Total commercial mortgage and other loans$11,960 100.0 $10,734 100.0 
Allowance for credit losses(174)(180)
              Total net commercial mortgage and other loans$11,786 $10,554 

Commercial mortgage and transitional real estate loans were secured by properties entirely within the U.S. (with the largest concentrations in California (21%), Texas (12%) and Florida (8%)). Middle market loans are issued only to companies domiciled within the U.S. and Canada.

Transitional Real Estate Loans

Transitional real estate loans are commercial mortgage loans that are typically relatively short-term floating rate instruments secured by a first lien on the property. These loans provide funding for properties undergoing a change in their physical characteristics and/or economic profile and do not typically require any principal repayment prior to the maturity date. This loan portfolio is generally considered to be investment grade. As of December 31, 2021, the Company had $665 million in outstanding commitments to fund transitional real estate loans. These commitments are contingent on the final underwriting and due diligence to be performed.

Commercial Mortgage Loans

Commercial mortgage loans are typically fixed rate loans on commercial real estate with partial repayment of principal over the life of the loan with the remaining outstanding principal being repaid upon maturity. This loan portfolio is generally considered higher quality investment grade loans. As of December 31, 2021, the Company had no outstanding commitments to fund commercial mortgage loans. These commitments are contingent on the final underwriting and due diligence to be performed.
Middle Market Loans

Middle market loans are typically first lien senior secured cash flow loans to small to mid-size companies for working capital, refinancing, acquisition, and recapitalization. These loans are generally considered to be below investment grade. The carrying value for middle market loans included $11 million and $25 million for a short term credit facility that is reflected in other liabilities on the consolidated balance sheets, as of December 31, 2021, and 2020, respectively.

As of December 31, 2021, the Company had commitments of approximately $1.4 billion to fund future middle market loans. These commitments are contingent upon the availability of middle market loans that meet the Company's underwriting criteria.

Credit Quality Indicators

For TREs, the Company’s key credit quality indicator is loan-to-value (LTV). Given that TRE loans involve properties undergoing renovation or construction, loan-to-value provides the most insight into the credit risk of the loan. The Company monitors the performance of the loans periodically, but not less frequently than quarterly.

For CMLs, the Company’s key credit quality indicators include LTV and debt service coverage ratios (DSCR). LTV is calculated by dividing the current outstanding loan balance by the most recent estimated property value. DSCR is the most recently available operating income of the underlying property compared to the required debt service of the loan.

For MMLs and held-to-maturity fixed maturity securities, the Company’s key credit quality indicator is credit ratings. The Company’s held-to-maturity portfolio is composed of investment grade securities that are senior unsecured instruments, while its MMLs generally have below-investment-grade ratings but are typically senior secured instruments. The Company monitors the credit ratings periodically, but not less frequently than quarterly.

For the Company’s reinsurance recoverable balance, the key credit quality indicator is the credit rating of the Company’s reinsurance counterparty. The Company uses external credit ratings focused on the reinsurer’s financial strength and credit worthiness. The Company's reinsurance counterparties are rated A+. The Company monitors the credit ratings periodically, but not less frequently than quarterly.
The following tables present as of December 31, 2021 the amortized cost basis of TREs, CMLs and MMLs by year of origination and credit quality indicator.
Transitional Real Estate Loans
(In millions)20212020201920182017PriorTotal
Loan-to-Value Ratio:
0%-59.99%$866 $36 $502 $85 $0 $0 $1,489 
60%-69.99%620 136 840 465 50 0 2,111 
70%-79.99%846 153 312 279 73 0 1,663 
80% or greater68 28 0 0 0 0 96 
Total$2,400 $353 $1,654 $829 $123 $0 $5,359 

Commercial Mortgage Loans
(In millions)20212020201920182017PriorTotalWeighted-Average DSCR
Loan-to-Value Ratio:
0%-59.99%$306 $47 $522 $167 $68 $535 $1,645 2.53
60%-69.99%34 0 86 0 0 114 234 1.92
70%-79.99%0 0 0 0 0 25 25 1.65
80% or greater0 0 0 0 0 0 0 0.00
Total$340 $47 $608 $167 $68 $674 $1,904 2.45
Weighted Average DSCR2.831.932.462.292.752.30
Middle Market Loans
(In millions)20212020201920182017PriorRevolving LoansTotal
Credit Ratings:
BBB$136 $67 $43 $24 $0 $0 $72 $342 
BB353 332 234 134 42 24 275 1,394 
B721 482 568 267 179 111 246 2,574 
CCC0 22 64 60 79 47 74 346 
CC0 0 0 14 26 0 1 41 
C and lower0 0 0 0 0 0 0 0 
Total$1,210 $903 $909 $499 $326 $182 $668 $4,697 

Allowance for Credit Losses

The Company calculates its allowance for credit losses for held-to-maturity fixed maturity securities, loan receivables, loan commitments and reinsurance recoverable by grouping assets with similar risk characteristics when there is not a specific expectation of a loss for an individual asset. For held-to-maturity fixed maturity securities, MMLs, and MML commitments, the Company groups assets by credit ratings, industry, and country. The Company groups CMLs and TREs and respective loan commitments by property type, property location and the property’s loan-to-value and debt service coverage ratios. The credit allowance for the reinsurance recoverable balance is estimated using a probability-of-default (PD) / loss-given-default (LGD) method.

The credit allowance for held-to-maturity fixed maturity securities and loan receivables is estimated using a PD / LGD method, discounted for the time value of money. For held-to-maturity fixed maturity securities, available-for-sale fixed maturity securities and loan receivables, the Company includes the change in present value due to the passage of time in the change in the allowance for credit losses. The Company’s methodology for estimating credit losses utilizes the contractual maturity date of the financial asset, adjusted when necessary to reflect the expected timing of repayment (such as prepayment options, renewal options, call options, or extension options). The Company applies reasonable and supportable forecasts of macroeconomic variables that impact the determination of PD/LGD over a two-year period for held-to-maturity fixed maturity securities and MMLs. The Company reverts to historical loss information over one year,
following the two-year forecast period. For the CML and TRE portfolio, the Company applies reasonable and supportable forecasts of macroeconomic variables as well as national and local real-estate market factors to estimate future credit losses where the market factors revert back to historical levels over time with the period being dependent on current market conditions, projected market conditions and difference in the current and historical market levels for each factor. The Company continuously monitors the estimation methodology, due to changes in portfolio composition, changes in underwriting practices and significant events or conditions and makes adjustments as necessary.

The Company’s held-to-maturity fixed maturity portfolio includes Japan Government and Agency securities of $20.9 billion amortized cost as of December 31, 2021 that meet the requirements for zero-credit-loss expectation and therefore these asset classes have been excluded from the current expected credit loss measurement.

An investment in an available-for-sale fixed maturity security is impaired if the fair value falls below amortized cost. The Company regularly reviews its fixed maturity security investments portfolio for declines in fair value. The Company's debt impairment model focuses on the ultimate collection of the cash flows from its investments and whether the Company has the intent to sell or if it is more likely than not the Company would be required to sell the security prior to recovery of its amortized cost. The determination of the amount of impairments under this model is based upon the Company's periodic evaluation and assessment of known and inherent risks associated with the respective securities. Such evaluations and assessments are revised as conditions change and new information becomes available.

When determining the Company's intention to sell a security prior to recovery of its fair value to amortized cost, the Company evaluates facts and circumstances such as, but not limited to, future cash flow needs, decisions to reposition its security portfolio, and risk profile of individual investment holdings. The Company performs ongoing analyses of its liquidity needs, which includes cash flow testing of its policy liabilities, debt maturities, projected dividend payments, and other cash flow and liquidity needs.

The Company’s methodology for estimating credit losses for available-for-sale fixed maturity securities utilizes the discounted cash flow model, based on past events, current market conditions and future economic conditions, as well as industry analysis and credit ratings of the fixed maturity securities. In addition, the Company evaluates the specific issuer’s probability of default and expected recovery of its position in the event of default based on the underlying financial condition and assets of the borrower as well as seniority and/or security of other debt holders in the issuer when developing management’s best estimate of expected cash flows.

The Company granted certain loan modifications in its MML and TRE portfolios during the year ended December 31, 2021. As of December 31, 2021 these loan modifications did not have a material impact on the Company’s results of operations.

The Company had no troubled debt restructurings (TDRs) during the year ended December 31, 2021 and an immaterial amount of TDRs during the year ended December 31, 2020 due to COVID-19. For certain TDRs, modifications resulted in write-offs for certain loans where the modified loan resulted in a forgiveness of existing principal and are included in the rollforward of the allowance for credit losses below.

The Company designates nonaccrual status for a nonperforming debt security or a loan that is not generating its stated interest rate because of nonpayment of periodic interest by the borrower. The Company applies the cash basis method to record any payments received on non-accrual assets. The Company resumes the accrual of interest on fixed maturity securities and loans that are currently making contractual payments or for those that are not current where the borrower has paid timely (less than 30 days outstanding).

As of December 31, 2021 and 2020, the Company had an immaterial amount of loans and fixed maturity securities on nonaccrual status.

The following table presents the roll forward of the allowance for credit losses by portfolio segment for the years ended December 31.
(In millions)Transitional Real Estate LoansCommercial Mortgage LoansMiddle Market LoansHeld to Maturity SecuritiesAvailable for Sale SecuritiesReinsurance Recoverables
Balance at December 31, 2019 (1)
$(22)$(3)$(20)$0 $0 $0 
Transition impact to retained earnings(2)(8)(33)(10)0 (11)
(Addition to) release of allowance for credit
  losses		(39)(21)(41)0 (75)(1)
Write-offs, net of recoveries0 0 9 0 37 0 
Balance at December 31, 2020(63)(32)(85)(10)(38)(12)
(Addition to) release of allowance for credit
  losses		(5)22 (11)1 26 (2)
Write-offs, net of recoveries0 0 0 0 12 0 
Change in foreign exchange0 0 0 1 0 1 
Balance at December 31, 2021$(68)$(10)$(96)$(8)$0 $(13)
(1) U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only.

For assets that are subject to the credit loss measurement, the change in credit loss allowance will be significantly impacted by purchases and sales in those assets during the period as well as entering into new non-cancelable loan commitments. During the first quarter of 2020, the Company entered into a loan commitment with an external manager that met the requirements to recognize a credit loss on over $2.2 billion of loan commitments in MMLs over the next few years. The estimate of credit losses for loan commitments was $31 million and $35 million as of December 31, 2021, and 2020, respectively.

Other Investments
The table below reflects the composition of the carrying value for other investments as of December 31.
(In millions)20212020
Other investments:
Policy loans$236 $260 
Short-term investments (1)
1,726 1,139 
Limited partnerships1,858 1,004 
Other22 26 
Total other investments$3,842 $2,429 
(1) Includes securities lending collateral

The Parent Company invests in partnerships that specialize in rehabilitating historic structures or the installation of solar equipment in order to receive federal historic rehabilitation and solar tax credits. These investments are classified as limited partnerships and included in other investments in the consolidated balance sheet. The change in value of each investment is recorded as a reduction to net investment income. Tax credits generated by these investments are recorded as an income tax benefit in the consolidated statement of earnings.

As of December 31, 2021, the Company had $1.8 billion in outstanding commitments to fund alternative investments in limited partnerships.
Variable Interest Entities (VIEs)

As a condition of its involvement or investment in a VIE, the Company enters into certain protective rights and covenants that preclude changes in the structure of the VIE that would alter the creditworthiness of the Company's investment or its beneficial interest in the VIE.

For those VIEs other than certain unit trust structures, the Company's involvement is passive in nature. The Company has not, nor has it been, required to purchase any securities issued in the future by these VIEs.

The Company's ownership interest in VIEs is limited to holding the obligations issued by them. The Company has no direct or contingent obligations to fund the limited activities of these VIEs, nor does it have any direct or indirect financial guarantees related to the limited activities of these VIEs. The Company has not provided any assistance or any other type
of financing support to any of the VIEs it invests in, nor does it have any intention to do so in the future. For those VIEs in which the Company holds debt obligations, the weighted-average lives of the Company's notes are very similar to the underlying collateral held by these VIEs where applicable.

The Company's risk of loss related to its interests in any of its VIEs is limited to the carrying value of the related investments held in the VIE.

VIEs - Consolidated

The following table presents the cost or amortized cost, fair value and balance sheet caption in which the assets and liabilities of consolidated VIEs are reported as of December 31.
Investments in Consolidated Variable Interest Entities
  20212020
(In millions)
Amortized
Cost (1)
Fair
Value
Amortized
Cost (1)
Fair
Value
Assets:
Fixed maturity securities, available for sale$3,264 $4,490 $3,487 $4,596 
Commercial mortgage and other loans9,740 9,910 8,964 9,040 
Other investments (2)
1,535 1,535 826 826 
Other assets (3)
78 78 133 133 
Total assets of consolidated VIEs$14,617 $16,013 $13,410 $14,595 
Liabilities:
Other liabilities (3)
$414 $414 $231 $231 
Total liabilities of consolidated VIEs$414 $414 $231 $231 
(1) Net of allowance for credit losses
(2) Consists entirely of alternative investments in limited partnerships
(3) Consists entirely of derivatives

The Company is substantively the only investor in the consolidated VIEs listed in the table above. As the sole investor in these VIEs, the Company has the power to direct the activities of a variable interest entity that most significantly impact the entity's economic performance and is therefore considered to be the primary beneficiary of the VIEs that it consolidates. The Company also participates in substantially all of the variability created by these VIEs. The activities of these VIEs are limited to holding invested assets and foreign currency swaps, as appropriate, and utilizing the cash flows from these securities to service its investment. Neither the Company nor any of its creditors are able to obtain the underlying collateral of the VIEs unless there is an event of default or other specified event. For those VIEs that contain a swap, the Company is not a direct counterparty to the swap contracts and has no control over them. The Company's loss exposure to these VIEs is limited to its original investment. The Company's consolidated VIEs do not rely on outside or ongoing sources of funding to support their activities beyond the underlying collateral and swap contracts, if applicable. With the exception of its investment in unit trust structures, the underlying collateral assets and funding of the Company's consolidated VIEs are generally static in nature.

Investments in Unit Trust Structures

The Company also utilizes unit trust structures in its Aflac Japan segment to invest in various asset classes. As the sole investor of these VIEs, the Company is required to consolidate these trusts under U.S. GAAP.

VIEs - Not Consolidated

The table below reflects the amortized cost, fair value and balance sheet caption in which the Company's investment in VIEs not consolidated are reported as of December 31.
Investments in Variable Interest Entities Not Consolidated
20212020
(In millions)Amortized
Cost		Fair
Value		Amortized
Cost		Fair
Value
Assets:
Fixed maturity securities, available for sale$4,779 $5,864 $5,477 $6,767 
Other investments (1)
323 323 178 178 
Total investments in VIEs not consolidated$5,102 $6,187 $5,655 $6,945 
(1) Consists entirely of alternative investments in limited partnerships
Certain investments in VIEs that the Company is not required to consolidate are investments that are in the form of debt obligations from the VIEs that are irrevocably and unconditionally guaranteed by their corporate parents or sponsors. These VIEs are the primary financing vehicles used by their corporate sponsors to raise financing in the capital markets. The variable interests created by these VIEs are principally or solely a result of the debt instruments issued by them. The Company does not have the power to direct the activities that most significantly impact the entity's economic performance, nor does it have the obligation to absorb losses of the entity or the right to receive benefits from the entity. As such, the Company is not the primary beneficiary of these VIEs and is therefore not required to consolidate them.
Securities Lending and Pledged Securities

The Company lends fixed maturity and public equity securities to financial institutions in short-term security-lending transactions. These short-term security-lending arrangements increase investment income with minimal risk. The Company receives cash or other securities as collateral for such loans. The Company's security lending policy requires that the fair value of the securities received as collateral be 102% or more of the fair value of the loaned securities and that unrestricted cash received as collateral be 100% or more of the fair value of the loaned securities. The securities loaned continue to be carried as investment assets on the Company's balance sheet during the terms of the loans and are not reported as sales. For loans involving unrestricted cash or securities as collateral, the collateral is reported as an asset with a corresponding liability for the return of the collateral. For loans where the Company receives as collateral securities that the Company is not permitted to sell or repledge, the collateral is not reflected on the consolidated financial statements.
Details of collateral by loaned security type and remaining maturity of the agreements as of December 31 were as follows:
Securities Lending Transactions Accounted for as Secured Borrowings
Remaining Contractual Maturity of the Agreements
20212020
(In millions)
Overnight
and
Continuous(1)
Up to 30
days		Total
Overnight
and
Continuous(1)
Up to 30
days		Total
Securities lending transactions:
Fixed maturity securities:
Japan government and
  agencies		$0 $920 $920 $0 $0 $0 
Public utilities40 0 40 57 0 57 
Sovereign and supranational2 0 2 3 0 3 
Banks/financial institutions88 0 88 63 0 63 
Other corporate1,112 0 1,112 841 0 841 
          Total borrowings$1,242 $920 $2,162 $964 $0 $964 
Gross amount of recognized liabilities for securities
   lending transactions		$2,162 $964 
(1) The related loaned security, under the Company's U.S. securities lending program, can be returned to the Company at the transferee's discretion; therefore, they are classified as Overnight and Continuous.

In connection with securities lending, in addition to cash collateral received, the Company received from counterparties securities collateral of $6.8 billion and $6.7 billion at December 31, 2021 and 2020, respectively, which may not be sold or re-pledged, unless the counterparty is in default. Such securities collateral is not reflected on the consolidated financial statements.

The Company did not have any repurchase agreements or repurchase-to-maturity transactions outstanding as of December 31, 2021 and 2020, respectively.

Certain fixed maturity securities can be pledged as collateral as part of derivative transactions, or pledged to support state deposit requirements on certain investment programs. For additional information regarding pledged securities related to derivative transactions, see Note 4.

At December 31, 2021, debt securities with a fair value of $17 million were on deposit with regulatory authorities in the U.S. (including U.S. territories). The Company retains ownership of all securities on deposit and receives the related investment income.

For general information regarding the Company's investment accounting policies, see Note 1.
v3.22.0.1
DERIVATIVE INSTRUMENTS
 12 Months Ended
Dec. 31, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
DERIVATIVE INSTRUMENTS DERIVATIVE INSTRUMENTS
The Company's freestanding derivative financial instruments have historically consisted of:
•foreign currency forwards and options used in hedging foreign exchange risk on U.S. dollar-denominated investments in Aflac Japan's portfolio, with options used on a standalone basis and/or in a collar strategy

•foreign currency forwards and options used to economically hedge certain portions of forecasted cash flows denominated in yen and hedge the Company's long term exposure to a weakening yen

•cross-currency interest rate swaps, also referred to as foreign currency swaps, associated with certain senior notes and subordinated debentures

•foreign currency swaps that are associated with VIE bond purchase commitments, and investments in special-purpose entities, including VIEs where the Company is the primary beneficiary

•interest rate swaps used to economically hedge interest rate fluctuations in certain variable-rate investments

•interest rate swaptions used to hedge changes in the fair value associated with interest rate fluctuations for certain U.S. dollar-denominated available-for-sale fixed-maturity securities
•bond purchase commitments at the inception of investments in consolidated VIEs.

Some of the Company's derivatives are designated as cash flow hedges, fair value hedges or net investment hedges; however, other derivatives do not qualify for hedge accounting or the Company elects not to designate them as accounting hedges.

Derivative Types

Foreign currency forwards and options are executed for the Aflac Japan segment in order to hedge the currency risk on the carrying value of certain U.S. dollar-denominated investments. The average maturity of these forwards and options can change depending on factors such as market conditions and types of investments being held. In situations where the maturity of the forwards and options is shorter than the underlying investment being hedged, the Company may enter into new forwards and options near maturity of the existing derivative in order to continue hedging the underlying investment. In forward transactions, Aflac Japan agrees with another party to buy a fixed amount of yen and sell a corresponding amount of U.S. dollars at a specified future date. The Company also uses one-sided foreign currency put options to mitigate the settlement risk on U.S. dollar-denominated assets related to extreme foreign currency rate changes. From time to time, Aflac Japan also executes foreign currency option transactions in a collar strategy, where Aflac Japan agrees with another party to simultaneously purchase put options and sell call options. In the purchased put transactions, Aflac Japan obtains the option to buy a fixed amount of yen and sell a corresponding amount of U.S. dollars at a specified future date. In the sold call transactions, Aflac Japan agrees to sell a fixed amount of yen and buy a corresponding amount of U.S. dollars at a specified future date. The combination of purchasing the put option and selling the call option results in no net premium being paid (i.e. a costless or zero-cost collar). In 2021, the Company moved to a strategy that contains one-sided put options, fewer foreign currency forwards and no collars.

From time to time, the Company may also enter into foreign currency forwards and options to hedge the currency risk associated with the net investment in Aflac Japan. In these forward transactions, the Company agrees with another party to buy a fixed amount of U.S. dollars and sell a corresponding amount of yen at a specified price at a specified future date. In the option transactions, the Company may use a combination of foreign currency options to protect expected future cash flows by simultaneously purchasing yen put options (options that protect against a weakening yen) and selling yen call options (options that limit participation in a strengthening yen). The combination of these two actions create a zero-cost collar. Additionally, the Company enters into purchased options to hedge cash flows from the net investment in Aflac Japan.

The Company enters into foreign currency swaps pursuant to which it exchanges an initial principal amount in one currency for an initial principal amount of another currency, with an agreement to re-exchange the principal amounts at a future date. There may also be periodic exchanges of payments at specified intervals based on the agreed upon rates and notional amounts. Foreign currency swaps are used primarily in the consolidated VIEs in the Company's Aflac Japan portfolio to convert foreign-denominated cash flows to yen, the functional currency of Aflac Japan, in order to minimize cash flow fluctuations. The Company also uses foreign currency swaps to economically convert certain of its U.S. dollar-denominated senior note and subordinated debenture principal and interest obligations into yen-denominated obligations.

In order to reduce investment income volatility from its variable-rate investments, the Company enters into receive–fixed, pay–floating interest rate swaps. These derivatives are cleared and settled through a central clearinghouse.

Swaptions are used to mitigate the adverse impact resulting from significant changes in the fair value of U.S. dollar-denominated available-for-sale securities due to fluctuation in interest rates. In a payer swaption, the Company pays a premium to obtain the right, but not the obligation, to enter into a swap contract where it will pay a fixed rate and receive a floating rate. Interest rate swaption collars are combinations of two swaption positions. In order to maximize the efficiency of the collars while minimizing cost, a collar strategy is used whereby the Company purchases a long payer swaption (the Company purchases an option that allows it to enter into a swap where the Company will pay the fixed rate and receive the floating rate of the swap) and sells a short receiver swaption (the Company sells an option that provides the counterparty with the right to enter into a swap where the Company will receive the fixed rate and pay the floating rate of the swap). The combination of purchasing the long payer swaption and selling the short receiver swaption results in no net premium being paid (i.e. a costless or zero-cost collar).

Bond purchase commitments result from repackaged bond structures that are consolidated VIEs whereby there is a delay in the trade date and settlement date of the bond within the structure to ensure completion of all necessary legal agreements to support the consolidated VIE that issues the repackaged bond. Since the Company has a commitment to purchase the underlying bond at a specified price, the agreement meets the definition of a derivative where the value is
derived based on the current market value of the bond compared to the fixed purchase price to be paid on the settlement date.

Derivative Balance Sheet Classification
The table below summarizes the balance sheet classification of the Company's derivative fair value amounts, as well as the gross asset and liability fair value amounts, at December 31. The fair value amounts presented do not include income accruals. Derivative assets are included in “Other Assets,” while derivative liabilities are included in “Other Liabilities” within the Company’s Consolidated Balance Sheets. The notional amount of derivative contracts represents the basis upon which pay or receive amounts are calculated and are not reflective of exposure or credit risk.
20212020
(In millions)Asset
Derivatives		Liability
Derivatives		Asset
Derivatives		Liability
Derivatives
Hedge Designation/ Derivative
  Type		Notional
Amount		Fair ValueFair ValueNotional
Amount		Fair ValueFair Value
Cash flow hedges:
Foreign currency swaps - VIE$18 $0 $2 $18 $0 $1 
Total cash flow hedges18 0 2 18 0 1 
Fair value hedges:
Foreign currency forwards62 0 5 64 2 0 
Foreign currency options8,829 5 0 8,865 0 0 
Total fair value hedges8,891 5 5 8,929 2 0 
Net investment hedge:
Foreign currency forwards4,996 341 0 5,010 14 84 
Foreign currency options1,949 0 0 2,027 1 0 
Total net investment hedge6,945 341 0 7,037 15 84 
Non-qualifying strategies:
Foreign currency swaps2,250 59 13 2,250 47 81 
Foreign currency swaps - VIE3,151 78 412 2,857 133 230 
Foreign currency forwards15,953 450 1,133 26,528 386 301 
Foreign currency options2,746 3 0 11,037 0 0 
Interest rate swaps3,500 0 54 0 0 0 
Total non-qualifying strategies27,600 590 1,612 42,672 566 612 
Total derivatives$43,454 $936 $1,619 $58,656 $583 $697 

Cash Flow Hedges

For certain variable-rate U.S. dollar-denominated available-for-sale securities held by Aflac Japan via consolidated VIEs, foreign currency swaps are used to swap the U.S. Dollar (USD) variable rate interest and principal payments to fixed rate Japanese Yen (JPY) interest and principal payments. The Company has designated foreign currency swaps as a hedge of the variability in cash flows of a forecasted transaction or of amounts to be received or paid related to a recognized asset (“cash flow” hedge). The remaining maximum length of time for which these cash flows are hedged is approximately five years. The derivatives in the Company's consolidated VIEs that are not designated as accounting hedges are discussed in the "non-qualifying strategies" section of this note.
Fair Value Hedges
The Company designates and accounts for certain foreign currency forwards, options, and interest rate swaptions as fair value hedges when they meet the requirements for hedge accounting. The Company recognizes gains and losses on these derivatives as well as the offsetting gain or loss on the related hedged items in current earnings.

Foreign currency forwards and options hedge the foreign currency exposure of certain U.S. dollar-denominated available-for-sale fixed-maturity investments held in Aflac Japan. The change in the fair value of the foreign currency forwards related to the changes in the difference between the spot rate and the forward price is excluded from the assessment of
hedge effectiveness. The change in fair value of the foreign currency option related to the time value of the option is recognized in current earnings and is excluded from the assessment of hedge effectiveness.

Interest rate swaptions hedge the interest rate exposure of certain U.S. dollar-denominated available-for-sale securities held in Aflac Japan. For these hedging relationships, the Company excludes time value from the assessment of hedge effectiveness and recognizes changes in the intrinsic value of the swaptions in current earnings within net investment income. The change in the time value of the swaptions is recognized in other comprehensive income (loss) and amortized into earnings (net investment income) over its legal term.

The following table presents the gains and losses on derivatives and the related hedged items in fair value hedges for the years ended December 31.
Fair Value Hedging Relationships
(In millions)Hedging DerivativesHedged Items
Hedging DerivativesHedged Items Total
Gains
(Losses)
Gains (Losses)
Excluded from Effectiveness Testing(1)
Gains (Losses)
Included in Effectiveness Testing(2)
 Gains (Losses)(2)
Net Investment Gains (Losses) Recognized for Fair Value Hedge
2021:
Foreign currency forwardsFixed maturity securities$(7)$0 $(7)$6 $(1)
Foreign currency optionsFixed maturity securities(26)(25)(1)4 3 
Total gains (losses)$(33)$(25)$(8)$10 $2 
2020:
Foreign currency forwardsFixed maturity securities$(14)$(8)$(6)$7 $1 
Foreign currency optionsFixed maturity securities(9)(8)(1)1 0 
Total gains (losses)$(23)$(16)$(7)$8 $1 
2019:
Foreign currency forwardsFixed maturity securities$(50)$(64)$14 $(12)$2 
Foreign currency optionsFixed maturity securities(7)(7)0 0 0 
Interest rate
swaptions		Fixed maturity securities(9)(9)0 0 0 
    Total gains (losses)$(66)$(80)$14 $(12)$2 
(1) Gains (losses) excluded from effectiveness testing includes the forward point on foreign currency forwards and time value change on foreign currency options which are reported in the consolidated statement of earnings as net investment gains (losses). It also includes the change in the fair value of the interest rate swaptions related to the time value of the swaptions which is recognized as a component of other comprehensive income (loss).
(2) Gains and losses on foreign currency forwards and options and related hedged items are reported in the consolidated statement of earnings as net investment gains (losses). For interest rate swaptions and related hedged items, gains and losses included in the hedge assessment, premium amortization and time value amortization while the hedge items are still outstanding are reported within net investment income. The time value gains and losses for interest rate swaptions when the related hedged items are redeemed are reported in net investment gains and losses consistent with the impact of the hedged item. For the years ended December 31, 2021 and 2020, gains and losses included in the hedge assessment on interest rate swaptions and related hedged items were immaterial.
The following table shows the carrying amounts of assets designated and qualifying as hedged items in fair value hedges of interest rate risk and the related cumulative hedge adjustment included in the carrying amount as of December 31.
(In millions)
Carrying Amount of the Hedged Assets/(Liabilities)(1)
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Assets/(Liabilities)
2021202020212020
Fixed maturity securities$3,038 $4,331 $205 $237 
(1) The balance includes hedging adjustment on discontinued hedging relationships of $205 in 2021 and $237 in 2020.

Net Investment Hedge

The Company's investment in Aflac Japan is affected by changes in the yen/dollar exchange rate. To mitigate this exposure, the Parent Company's yen-denominated liabilities (see Note 9) have been designated as non-derivative hedges and certain foreign currency forwards and options have been designated as derivative hedges of the foreign currency exposure of the Company's net investment in Aflac Japan.

The Company's net investment hedge was effective during the years ended December 31, 2021, 2020 and 2019.
Non-qualifying Strategies
For the Company's derivative instruments in consolidated VIEs that do not qualify for hedge accounting treatment, all changes in their fair value are reported in current period earnings within net investment gains (losses). The amount of gain or loss recognized in earnings for the Company's VIEs is attributable to the derivatives in those investment structures. While the change in value of the swaps is recorded through current period earnings, the change in value of the available-for-sale fixed maturity securities associated with these swaps is recorded through other comprehensive income.
As of December 31, 2021, the Parent Company had $2.3 billion notional amount of cross-currency interest rate swap agreements related to certain of its U.S. dollar-denominated senior notes to effectively convert a portion of the interest on the notes from U.S dollar to Japanese yen. Changes in the values of these swaps are recorded through current period earnings. For additional information regarding these swaps, see Note 9.
The Company uses foreign exchange forwards and options to economically mitigate the currency risk of some of its U.S. dollar-denominated loan receivables held within the Aflac Japan segment. These arrangements are not designated as accounting hedges, as the foreign currency remeasurement of the loan receivables impacts current period earnings, and substantially offsets gains and losses from foreign exchange forwards within net investment gains (losses). The Company also has certain foreign exchange forwards on U.S. dollar-denominated available-for-sale securities where hedge accounting is not being applied.

The Company uses interest rate swaps to economically convert the variable rate investment income to a fixed rate on certain variable-rate investments.
Impact of Derivatives and Hedging Instruments

The following table summarizes the impact to earnings and other comprehensive income (loss) from all derivatives and hedging instruments for the years ended December 31.
202120202019
(In millions)
Net Investment Income (1)
Net Investment
Gains (Losses)
Other
Comprehensive
Income (Loss)(2)
Net Investment Income (1)
Net Investment
Gains (Losses)
Other
Comprehensive
Income (Loss)(2)
Net Investment Income (1)
Net Investment
Gains (Losses)
Other
Comprehensive
Income (Loss)(2)
Qualifying hedges:
  Cash flow hedges:
       Foreign currency swaps - VIE$(1)$(4)$3 $(1)$0 $(2)$(2)$(1)$(4)
  Total cash flow hedges(1)(4)
(3)
3 (1)0 
(3)
(2)(2)(1)
(3)
(4)
  Fair value hedges:
       Foreign currency forwards (3)
(1)(7)(62)
       Foreign currency options (3)
(22)(8)(7)
       Interest rate swaptions (3)
(1)(1)2 (1)0 1 (1)0 (8)
  Total fair value hedges(1)(24)2 (1)(15)1 (1)(69)(8)
  Net investment hedge:
       Non-derivative hedging
          instruments		0 328 0 (135)0 (24)
       Foreign currency forwards29 525 149 (282)10 83 
       Foreign currency options (4)0 (5)0 (4)0 
   Total net investment hedge25 853 144 (417)6 59 
  Non-qualifying strategies:
       Foreign currency swaps135 29 90 
       Foreign currency swaps - VIE(188)(122)(68)
       Foreign currency forwards(707)311 (148)
       Foreign currency options (3)(3)0 
       Interest rate swaps(38)49 17 
Forward bond purchase
  commitment - VIE		(1)6 0 
  Total non-qualifying strategies(802)270 (110)
          Total$(2)$(805)$858 $(2)$399 $(418)$(3)$(174)$47 
(1) Interest expense/income on cash flow hedges are recorded in net investment income. For interest rate swaptions classified as fair value hedges, the change in the time value of the swaptions is recognized in other comprehensive income (loss) and amortized into net investment income over its legal term. If the swaption is early terminated but the hedge item is still outstanding, the amortization of disposal amount of the swaptions is recorded in net investment income over the remaining life of the hedged items.
(2) Gains and losses on cash flow hedges and the change in the fair value of interest rate swaptions related to the time value of the swaptions in fair value hedges are recorded as unrealized gains (losses). Gains and losses on net investment hedges related to changes in foreign currency spot rates are recorded in the unrealized foreign currency translation gains (losses) line in the consolidated statement of comprehensive income (loss).
(3) Impact of cash flow hedges reported as net investment gains (losses) includes $4 of losses reclassified from accumulated other comprehensive income (loss) into earnings during the year ended December 31, 2021, and an immaterial amount during the years ended December 31, 2020 and 2019, respectively. In addition, $2 of losses were reclassified from accumulated other comprehensive income (loss) into earnings during the year ended December 31, 2021, and an immaterial amount during the years ended December 31, 2020 and 2019, respectively, related to fair value hedges excluded component. Impact shown net of effect of hedged items (see Fair Value Hedges section of this Note 4 for further detail).
As of December 31, 2021, $5 million of deferred losses on derivative instruments recorded in accumulated other comprehensive income are expected to be reclassified into earnings during the next twelve months.

Credit Risk Assumed through Derivatives

For the foreign currency swaps associated with the Company's VIE investments for which it is the primary beneficiary, the Company bears the risk of loss due to counterparty default even though it is not a direct counterparty to those contracts.

The Company is a direct counterparty to the foreign currency swaps that it has entered into in connection with certain of its senior notes and subordinated debentures; foreign currency forwards; and foreign currency options, and therefore the Company is exposed to credit risk in the event of nonperformance by the counterparties in those contracts. The risk of counterparty default for the Company's foreign currency swaps, certain foreign currency forwards, and foreign currency options is mitigated by collateral posting requirements that counterparties to those transactions must meet.

As of December 31, 2021, all of the Company's derivative agreement counterparties were investment grade.

The Company engages in over-the-counter (OTC) bilateral derivative transactions directly with unaffiliated third parties under International Swaps and Derivatives Association, Inc. (ISDA) agreements and other documentation. Most of the ISDA agreements also include Credit Support Annexes (CSAs) provisions, which generally provide for two-way collateral postings at the first dollar of exposure. The Company mitigates the risk that counterparties to transactions might be unable to fulfill their contractual obligations by monitoring counterparty credit exposure and collateral value while generally requiring that collateral be posted at the outset of the transaction. In addition, a significant portion of the derivative transactions have provisions that give the counterparty the right to terminate the transaction upon a downgrade of the Company's financial strength rating. The actual amount of payments that the Company could be required to make depends on market conditions, the fair value of outstanding affected transactions, and other factors prevailing at and after the time of the downgrade.

The Company also engages in OTC cleared derivative transactions through regulated central clearing counterparties. These positions are marked to market and margined on a daily basis (both initial margin and variation margin), and the Company has minimal exposure to credit-related losses in the event of nonperformance by counterparties to these derivatives.

Collateral posted by the Company to third parties for derivative transactions can generally be repledged or resold by the counterparties. The aggregate fair value of all derivative instruments with credit-risk-related contingent features that were in a net liability position by counterparty was approximately $904 million and $268 million as of December 31, 2021 and 2020, respectively. If the credit-risk-related contingent features underlying these agreements had been triggered on December 31, 2021, the Company estimates that it would be required to post a maximum of $193 million of additional collateral to these derivative counterparties. The Company is generally allowed to sell or repledge collateral obtained from its derivative counterparties, although it does not typically exercise such rights. (See the Offsetting tables below for collateral posted or received as of the reported balance sheet dates.)

Offsetting of Financial Instruments and Derivatives

Most of the Company's derivative instruments are subject to enforceable master netting arrangements that provide for the net settlement of all derivative contracts between the Parent Company or its subsidiaries and the respective counterparty in the event of default or upon the occurrence of certain termination events. Collateral support agreements with the master netting arrangements generally provide that the Company will receive or pledge financial collateral at the first dollar of exposure.

The Company has securities lending agreements with unaffiliated financial institutions that post collateral to the Company in return for the use of its fixed maturity and public equity securities (see Note 3). When the Company has entered into securities lending agreements with the same counterparty, the agreements generally provide for net settlement in the event of default by the counterparty. This right of set-off allows the Company to keep and apply collateral received if the counterparty failed to return the securities borrowed from the Company as contractually agreed. For additional information on the Company's accounting policy for securities lending, see Note 1.

The tables below summarize the Company's derivatives and securities lending transactions as of December 31, and as reflected in the tables, in accordance with U.S. GAAP, the Company's policy is to not offset these financial instruments in the Consolidated Balance Sheets.
Offsetting of Financial Assets and Derivative Assets
2021
Gross Amounts Not Offset
in Balance Sheet
(In millions)Gross Amount of Recognized AssetsGross Amount Offset in Balance SheetNet Amount of Assets Presented
 in Balance Sheet		Financial InstrumentsSecurities
Collateral		Cash Collateral ReceivedNet
 Amount
Derivative
  assets:
    Derivative
      assets subject to a
      master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral$858 $0 $858 $(471)$(53)$(334)$0 
    Total derivative
      assets subject to a
      master netting
      agreement or
      offsetting
      arrangement		858 0 858 (471)(53)(334)0 
    Derivative
      assets not subject
      to a master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral78 78 78 
    Total derivative
      assets not subject
      to a master netting
      agreement or
      offsetting
      arrangement		78 78 78 
    Total derivative
      assets		936 0 936 (471)(53)(334)78 
Securities lending
   and similar
   arrangements		2,124 0 2,124 0 0 (2,124)0 
    Total$3,060 $0 $3,060 $(471)$(53)$(2,458)$78 
2020
Gross Amounts Not Offset
in Balance Sheet
(In millions)Gross Amount of Recognized AssetsGross Amount Offset in Balance SheetNet Amount of Assets Presented in Balance SheetFinancial
Instruments		Securities CollateralCash Collateral ReceivedNet
 Amount
Derivative
  assets:
    Derivative
      assets subject to a
      master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral$450 $0 $450 $(295)$(73)$(76)$6 
    Total derivative
      assets subject to a
      master netting
      agreement or
      offsetting
      arrangement		450 0 450 (295)(73)(76)6 
    Derivative
      assets not subject
      to a master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral133 133 133 
    Total derivative
      assets not subject
      to a master netting
      agreement or
      offsetting
      arrangement		133 133 133 
    Total derivative
      assets		583 0 583 (295)(73)(76)139 
Securities lending
   and similar
   arrangements		940 0 940 0 0 (940)0 
    Total$1,523 $0 $1,523 $(295)$(73)$(1,016)$139 
Offsetting of Financial Liabilities and Derivative Liabilities
2021
Gross Amounts Not Offset
in Balance Sheet
(In millions)Gross Amount of Recognized LiabilitiesGross Amount Offset in Balance SheetNet Amount of Liabilities Presented in Balance SheetFinancial InstrumentsSecurities CollateralCash Collateral PledgedNet
 Amount
Derivative
  liabilities:
    Derivative
      liabilities subject
      to a master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral$1,151 $0 $1,151 $(471)$(662)$(14)$4 
          OTC - cleared54 0 54 0 0 (35)19 
    Total derivative
      liabilities subject
      to a master netting
      agreement or
      offsetting
      arrangement		1,205 0 1,205 (471)(662)(49)23 
    Derivative
      liabilities not
      subject to a
      master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral414 414 414 
    Total derivative
      liabilities not
      subject to a
      master netting
      agreement or
      offsetting
      arrangement		414 414 414 
    Total derivative
      liabilities		1,619 0 1,619 (471)(662)(49)437 
Securities lending
   and similar
   arrangements		2,162 0 2,162 (2,124)0 0 38 
    Total$3,781 $0 $3,781 $(2,595)$(662)$(49)$475 
2020
Gross Amounts Not Offset
in Balance Sheet
(In millions)Gross Amount of Recognized LiabilitiesGross Amount Offset in Balance SheetNet Amount of Liabilities Presented in Balance SheetFinancial InstrumentsSecurities CollateralCash Collateral PledgedNet
 Amount
Derivative
  liabilities:
    Derivative
      liabilities subject
      to a master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral$466 $0 $466 $(295)$(43)$(69)$59 
    Total derivative
      liabilities subject
      to a master netting
      agreement or
      offsetting
      arrangement		466 0 466 (295)(43)(69)59 
    Derivative
      liabilities not
      subject to a
      master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral231 231 231 
    Total derivative
      liabilities not
      subject to a
      master netting
      agreement or
      offsetting
      arrangement		231 231 231 
    Total derivative
      liabilities		697 0 697 (295)(43)(69)290 
Securities lending
   and similar
   arrangements		964 0 964 (940)0 0 24 
    Total$1,661 $0 $1,661 $(1,235)$(43)$(69)$314 

For additional information on the Company's financial instruments, see the accompanying Notes 1, 3 and 5.
v3.22.0.1
FAIR VALUE MEASUREMENTS
 12 Months Ended
Dec. 31, 2021
Fair Value Disclosures [Abstract]  
FAIR VALUE MEASUREMENTS FAIR VALUE MEASUREMENTS
Fair Value Hierarchy

U.S. GAAP specifies a hierarchy of valuation techniques based on whether the inputs to those valuation techniques are observable or unobservable. These two types of inputs create three valuation hierarchy levels. Level 1 valuations reflect quoted market prices for identical assets or liabilities in active markets. Level 2 valuations reflect quoted market prices for similar assets or liabilities in an active market, quoted market prices for identical or similar assets or liabilities in non-active markets or model-derived valuations in which all significant valuation inputs are observable in active markets. Level 3 valuations reflect valuations in which one or more of the significant inputs are not observable in an active market.

The following tables present the fair value hierarchy levels of the Company's assets and liabilities that are measured and carried at fair value on a recurring basis as of December 31.
  2021
(In millions)Quoted Prices in
Active Markets
for Identical
Assets
(Level 1)		Significant
Observable
Inputs
(Level 2)		Significant
Unobservable
Inputs
(Level 3)		Total
Fair
Value
Assets:
Securities available for sale, carried at
  fair value:
Fixed maturity securities:
Government and agencies$32,532 $1,288 $0 $33,820 
Municipalities0 3,036 0 3,036 
Mortgage- and asset-backed securities0 955 291 1,246 
Public utilities0 9,558 493 10,051 
Sovereign and supranational0 1,072 43 1,115 
Banks/financial institutions0 11,546 45 11,591 
Other corporate0 37,411 426 37,837 
Total fixed maturity securities32,532 64,866 1,298 98,696 
Equity securities1,340 90 173 1,603 
Other investments1,726 0 0 1,726 
Cash and cash equivalents5,051 0 0 5,051 
Other assets:
Foreign currency swaps0 137 0 137 
Foreign currency forwards0 791 0 791 
Foreign currency options0 8 0 8 
Total other assets0 936 0 936 
Total assets$40,649 $65,892 $1,471 $108,012 
Liabilities:
Other liabilities:
Foreign currency swaps$0 $427 $0 $427 
Foreign currency forwards0 1,138 0 1,138 
Interest rate swaps0 54 0 54 
Total liabilities$0 $1,619 $0 $1,619 
  2020
(In millions)Quoted Prices in
Active Markets
for Identical
Assets
(Level 1)		Significant
Observable
Inputs
(Level 2)		Significant
Unobservable
Inputs
(Level 3)		Total
Fair
Value
Assets:
Securities available for sale, carried at
  fair value:
Fixed maturity securities:
Government and agencies$36,032 $1,318 $0 $37,350 
Municipalities0 3,018 0 3,018 
Mortgage- and asset-backed securities0 814 224 1,038 
Public utilities0 10,395 422 10,817 
Sovereign and supranational0 1,334 48 1,382 
Banks/financial institutions0 12,036 24 12,060 
Other corporate0 39,918 299 40,217 
Total fixed maturity securities36,032 68,833 1,017 105,882 
Equity securities1,095 86 102 1,283 
Other investments1,139 0 0 1,139 
Cash and cash equivalents5,141 0 0 5,141 
Other assets:
Foreign currency swaps0 47 133 180 
Foreign currency forwards0 402 0 402 
Foreign currency options0 1 0 1 
Total other assets0 450 133 583 
Total assets$43,407 $69,369 $1,252 $114,028 
Liabilities:
Other liabilities:
Foreign currency swaps$0 $81 $231 $312 
Foreign currency forwards0 385 0 385 
Total liabilities$0 $466 $231 $697 
The following tables present the carrying amount and fair value categorized by fair value hierarchy level for the Company's financial instruments that are not carried at fair value as of December 31.
2021
(In millions)Carrying
Value		Quoted Prices in
Active Markets
for Identical
Assets
(Level 1)		Significant
Observable
Inputs
(Level 2)		Significant
Unobservable
Inputs
(Level 3)		Total
Fair
Value
Assets:
Securities held to maturity,
    carried at amortized cost:
  Fixed maturity securities:
Government and agencies$21,086 $25,469 $230 $0 $25,699 
Municipalities335 0 436 0 436 
Public utilities43 0 55 0 55 
Sovereign and
   supranational		514 0 650 0 650 
Other corporate22 0 29 0 29 
Commercial mortgage and
    other loans		11,786 0 0 11,996 11,996 
Other investments (1)
22 0 22 0 22 
 Total assets$33,808 $25,469 $1,422 $11,996 $38,887 
Liabilities:
Other policyholders’ funds$7,072 $0 $0 $6,957 $6,957 
Notes payable
   (excluding leases)		7,839 0 8,280 259 8,539 
Total liabilities$14,911 $0 $8,280 $7,216 $15,496 
(1) Excludes policy loans of $236 and equity method investments of $1,858, at carrying value
2020
(In millions)Carrying
Value		Quoted Prices in
Active Markets
for Identical
Assets
(Level 1)		Significant
Observable
Inputs
(Level 2)		Significant
Unobservable
Inputs
(Level 3)		Total
Fair
Value
Assets:
Securities held to maturity,
   carried at amortized cost:
  Fixed maturity securities:
Government and agencies$23,445 $28,810 $260 $0 $29,070 
Municipalities377 0 499 0 499 
Public utilities47 0 61 0 61 
Sovereign and
   supranational		571 0 736 0 736 
Other corporate24 0 33 0 33 
Commercial mortgage and
    other loans		10,554 0 0 10,655 10,655 
Other investments (1)
26 0 26 0 26 
  Total assets$35,044 $28,810 $1,615 $10,655 $41,080 
Liabilities:
Other policyholders’ funds$7,824 $0 $0 $7,709 $7,709 
Notes payable
   (excluding leases)		7,745 0 8,396 288 8,684 
Total liabilities$15,569 $0 $8,396 $7,997 $16,393 
(1) Excludes policy loans of $260 and equity method investments of $1,004, at carrying value

Fair Value of Financial Instruments

Fixed maturity and equity securities

The Company determines the fair values of fixed maturity securities and public and privately-issued equity securities using the following approaches or techniques: price quotes and valuations from third party pricing vendors (including quoted market prices readily available from public exchange markets), in-house valuations and non-binding price quotes the Company obtains from outside brokers.

A third party pricing vendor has developed valuation models to determine fair values of privately issued securities. Starting in June 2021, these models and associated processes and controls were transitioned to and executed by Company personnel. These models are discounted cash flow (DCF) valuation models, but also use information from related markets, specifically the CDS market to estimate expected cash flows. These models take into consideration any unique characteristics of the securities and make various adjustments to arrive at an appropriate issuer-specific loss adjusted credit curve. This credit curve is then used with the relevant recovery rates to estimate expected cash flows and modeling of additional features, including illiquidity adjustments, if necessary, to price the security by discounting those loss adjusted cash flows. In cases where a credit curve cannot be developed from the specific security features, the valuation methodology takes into consideration other market observable inputs, including:
1) the most appropriate comparable security(ies) of the issuer
2) issuer-specific CDS spreads
3) bonds or CDS spreads of comparable issuers with similar characteristics such as rating, geography, or sector
4) bond indices that are comparative in rating, industry, maturity and region.

The pricing data and market quotes the Company obtains from outside sources, including third party pricing services, are reviewed internally for reasonableness. If a fair value appears unreasonable, the Company will re-examine the inputs and assess the reasonableness of the pricing data with the vendor. Additionally, the Company may compare the inputs to relevant market indices and other performance measurements. Based on management's analysis, the valuation is confirmed or may be revised if there is evidence of a more appropriate estimate of fair value based on available market data. Beginning in the third quarter of 2020, the Company refined these valuation models to explicitly incorporate currency
basis swap adjustments (market observable data) to assumed interest rate curves where appropriate. The Company has performed verification of the inputs and calculations in any valuation models to confirm that the valuations represent reasonable estimates of fair value.

For the periods presented, the Company has not adjusted the quotes or prices it obtains from the pricing services and brokers it uses.

The following tables present the pricing sources for the fair values of the Company's fixed maturity and equity securities as of December 31.
2021
(In millions)Quoted Prices in Active Markets for Identical Assets
(Level 1)		Significant Observable Inputs
(Level 2)		Significant Unobservable Inputs
(Level 3)		Total
Fair
Value
Securities available for sale, carried at fair value:
      Fixed maturity securities:
         Government and agencies:
Third party pricing vendor$32,532 $808 $0 $33,340 
Internal0 480 0 480 
               Total government and agencies32,532 1,288 0 33,820 
         Municipalities:
Third party pricing vendor0 2,222 0 2,222 
Internal0 814 0 814 
               Total municipalities0 3,036 0 3,036 
         Mortgage- and asset-backed securities:
Third party pricing vendor0 955 0 955 
Broker/other0 0 291 291 
               Total mortgage- and asset-backed securities0 955 291 1,246 
         Public utilities:
Third party pricing vendor0 4,527 0 4,527 
Internal 0 5,031 0 5,031 
Broker/other0 0 493 493 
               Total public utilities0 9,558 493 10,051 
         Sovereign and supranational:
Third party pricing vendor0 273 0 273 
Internal0 799 0 799 
Broker/other0 0 43 43 
               Total sovereign and supranational0 1,072 43 1,115 
         Banks/financial institutions:
Third party pricing vendor0 5,237 0 5,237 
Internal0 6,309 0 6,309 
Broker/other0 0 45 45 
               Total banks/financial institutions0 11,546 45 11,591 
         Other corporate:
Third party pricing vendor0 29,495 0 29,495 
Internal0 7,916 0 7,916 
Broker/other0 0 426 426 
               Total other corporate0 37,411 426 37,837 
                  Total securities available for sale$32,532 $64,866 $1,298 $98,696 
Equity securities, carried at fair value:
Third party pricing vendor$1,340 $90 $0 $1,430 
Broker/other0 0 173 173 
               Total equity securities$1,340 $90 $173 $1,603 
2021
(In millions)Quoted Prices in Active Markets for Identical Assets
(Level 1)		Significant Observable Inputs
(Level 2)		Significant Unobservable Inputs
(Level 3)		Total
Fair
 Value
Securities held to maturity, carried at amortized cost:
      Fixed maturity securities:
         Government and agencies:
Third party pricing vendor$25,469 $230 $0 $25,699 
               Total government and agencies25,469 230 0 25,699 
         Municipalities:
Third party pricing vendor0 436 0 436 
               Total municipalities0 436 0 436 
         Public utilities:
Third party pricing vendor0 55 0 55 
               Total public utilities0 55 0 55 
         Sovereign and supranational:
Third party pricing vendor0 313 0 313 
Broker/other0 337 0 337 
               Total sovereign and supranational0 650 0 650 
         Other corporate:
Third party pricing vendor0 29 0 29 
               Total other corporate0 29 0 29 
                  Total securities held to maturity$25,469 $1,400 $0 $26,869 
2020
(In millions)Quoted Prices in Active Markets
for Identical Assets
(Level 1)		Significant Observable
Inputs
(Level 2)		Significant Unobservable Inputs
(Level 3)		Total
Fair
Value
Securities available for sale, carried at fair value:
      Fixed maturity securities:
         Government and agencies:
Third party pricing vendor$36,032 $1,318 $0 $37,350 
               Total government and agencies36,032 1,318 0 37,350 
         Municipalities:
Third party pricing vendor0 3,018 0 3,018 
               Total municipalities0 3,018 0 3,018 
         Mortgage- and asset-backed securities:
Third party pricing vendor0 364 0 364 
Broker/other0 450 224 674 
               Total mortgage- and asset-backed securities0 814 224 1,038 
         Public utilities:
Third party pricing vendor0 10,395 0 10,395 
Broker/other0 0 422 422 
               Total public utilities0 10,395 422 10,817 
         Sovereign and supranational:
Third party pricing vendor0 1,334 0 1,334 
Broker/other0 0 48 48 
               Total sovereign and supranational0 1,334 48 1,382 
         Banks/financial institutions:
Third party pricing vendor0 12,036 0 12,036 
Broker/other0 0 24 24 
               Total banks/financial institutions0 12,036 24 12,060 
         Other corporate:
Third party pricing vendor0 39,886 0 39,886 
Broker/other0 32 299 331 
               Total other corporate0 39,918 299 40,217 
                  Total securities available for sale$36,032 $68,833 $1,017 $105,882 
Equity securities, carried at fair value:
Third party pricing vendor$1,095 $86 $0 $1,181 
Broker/other0 0 102 102 
               Total equity securities$1,095 $86 $102 $1,283 
2020
(In millions)Quoted Prices in Active Markets
for Identical Assets
(Level 1)		Significant Observable
Inputs
(Level 2)		Significant Unobservable Inputs
(Level 3)		Total
Fair
 Value
Securities held to maturity, carried at amortized cost:
      Fixed maturity securities:
         Government and agencies:
Third party pricing vendor$28,810 $260 $0 $29,070 
               Total government and agencies28,810 260 0 29,070 
         Municipalities:
Third party pricing vendor0 499 0 499 
               Total municipalities0 499 0 499 
         Public utilities:
Third party pricing vendor0 61 0 61 
               Total public utilities0 61 0 61 
         Sovereign and supranational:
Third party pricing vendor0 736 0 736 
               Total sovereign and supranational0 736 0 736 
         Other corporate:
Third party pricing vendor0 33 0 33 
               Total other corporate0 33 0 33 
                  Total securities held to maturity$28,810 $1,589 $0 $30,399 

The following is a discussion of the determination of fair value of the Company's remaining financial instruments.

Derivatives

The Company uses derivative instruments to manage the risk associated with certain assets. However, the derivative instrument may not be classified in the same fair value hierarchy level as the associated asset. The significant inputs to pricing derivatives are generally observable in the market or can be derived by observable market data. When these inputs are observable, the derivatives are classified as Level 2.

The Company uses present value techniques to value non-option based derivatives. It also uses option pricing models to value option based derivatives. Key inputs are as follows:
Instrument TypeLevel 2Level 3
Interest rate derivatives
Swap yield curves
Basic curves
Interest rate volatility (1)
Not applicable
Foreign currency exchange rate derivatives - Non-VIES (forwards, swaps and options)
Foreign currency forward rates
Swap yield curves
Basis curves
Foreign currency spot rates
Cross foreign currency basis curves
Foreign currency volatility (1)
Not applicable
Foreign currency exchange rate derivatives - VIEs (swaps)
Foreign currency spot rates
Swap yield curves
Credit default swap curves
Basis curves
Recovery rates
Foreign currency forward rates
Foreign cross currency basis curves
Not applicable
(1) Option-based only
The fair values of the foreign currency forwards and options are based on observable market inputs, therefore they are classified as Level 2.

The Parent Company has cross-currency swap agreements related to certain of its U.S. dollar-denominated senior notes to effectively convert a portion of the interest on the notes from U.S dollar to Japanese yen. Their fair values are based on observable market inputs, therefore they are classified as Level 2.

To determine the fair value of its interest rate derivatives, the Company uses inputs that are generally observable in the market or can be derived from observable market data. Interest rate swaps are cleared trades. In a cleared swap contract, the clearinghouse provides benefits to the counterparties similar to contracts listed for investment traded on an exchange since it maintains a daily margin to mitigate counterparties' credit risk. These derivatives are priced using observable inputs, accordingly, they are classified as Level 2. For its interest rate swaptions, the Company estimates their fair values using observable market data, including interest rate curves and volatility. Their fair values are also classified as Level 2.

For derivatives associated with VIEs where the Company is the primary beneficiary, the Company is not the direct counterparty to the swap contracts. Nevertheless, the Company has full transparency into the contracts to properly value the swaps for reporting purposes. Prior to October 1, 2021, these derivatives were classified as Level 3 because certain significant inputs were determined to be unobservable, primarily due to the long duration of the swaps which required extrapolation beyond the observable limits of the curve(s). However, due to the natural aging of the swap portfolio and the continued evolution of capital market inputs, especially the availability of long-term interest rates with tenors beyond 30 years, the Company has concluded that all significant inputs are now observable. As a result, effective October 1, 2021, the Company transferred the derivatives associated with its consolidated VIEs to Level 2 of the fair value hierarchy.

For forward bond purchase commitments with VIEs, the fair value of the derivative is based on the difference in the fixed purchase price and the current market value of the related bond prior to the settlement date. Since the bond is typically a public bond with readily available pricing, the derivatives associated with the forward purchase commitment are classified as Level 2 of the fair value hierarchy.

Commercial mortgage and other loans

Commercial mortgage and other loans include TREs, CMLs and MMLs. The Company's loan receivables do not have readily determinable market prices and generally lack market liquidity. Fair values for loan receivables are determined based on the present value of expected future cash flows discounted at the applicable U.S. Treasury or floating-rate benchmark yield plus an appropriate spread that considers other risk factors, such as credit and liquidity risk. The spreads are a significant component of the pricing inputs and are generally considered unobservable. Therefore, these investments have been assigned a Level 3 within the fair value hierarchy.

Other investments

Other investments includes short-term investments that are measured at fair value where amortized cost approximates fair value.

Other policyholders' funds

The largest component of the other policyholders' funds liability is the Company's annuity line of business in Aflac Japan. The Company's annuities have fixed benefits and premiums. For this product, the Company estimates the fair value to be equal to the cash surrender value. This is analogous to the value paid to policyholders on the valuation date if they were to surrender their policy. The Company periodically checks the cash value against discounted cash flow projections for reasonableness. The Company considers its inputs for this valuation to be unobservable and have accordingly classified this valuation as Level 3.

Notes payable
The fair values of the Company's publicly issued notes payable are determined by utilizing available sources of observable inputs from third party pricing vendors and are classified as Level 2. The fair values of the Company's yen-denominated loans approximate their carrying values and are classified as Level 3.
Transfers between Hierarchy Levels and Level 3 Rollforward

Assets and liabilities are transferred into Level 3 when a significant input cannot be corroborated with market observable data. This occurs when market activity decreases significantly and underlying inputs cannot be observed, current prices are not available, and/or when there are significant variances in quoted prices, thereby affecting transparency. Assets and liabilities are transferred out of Level 3 when circumstances change such that a significant input can be corroborated with market observable data. This may be due to a significant increase in market activity, a specific event, or one or more significant input(s) becoming observable. Effective October 1, 2021, the foreign exchange swaps discussed above were transferred from Level 3 to Level 2 because the significant inputs used for their valuation that were previously unobservable are now observable.

The following tables present the changes in fair value of the Company's investments and derivatives carried at fair value classified as Level 3 as of December 31. Derivative assets and liabilities are presented as a net value.
2021
 Fixed Maturity SecuritiesEquity
Securities		Derivatives
(In millions)Mortgage-
and
Asset-
Backed
Securities		Public
Utilities		Sovereign
and
Supranational		Banks/
Financial
Institutions		Other
Corporate		 Foreign
Currency
Swaps		Total
Balance, beginning of period$224 $422 $48 $24 $299 $102 $(98)$1,021 
Net investment gains (losses) included
  in earnings		0 0 0 0 2 21 (158)(135)
Unrealized gains (losses) included in
  other comprehensive income (loss)		(25)(21)(5)(2)(11)0 (1)(65)
Purchases, issuances, sales
  and settlements:
Purchases169 167 0 23 90 41 0 490 
Issuances0 0 0 0 0 17 0 17 
Sales0 (2)(23)0 0 (8)0 (33)
Settlements0 (21)0 0 (17)0 0 (38)
Transfers into Level 30 0 23 0 84 0 0 107 
Transfers out of Level 3(77)(52)0 0 (21)0 257 107 
Balance, end of period$291 $493 $43 $45 $426 $173 $0 $1,471 
Changes in unrealized gains (losses)
  relating to Level 3 assets and liabilities
  still held at the end of the period
  included in earnings		$(24)$(23)$(4)$(2)$(27)$21 $(158)$(217)
2020
  Fixed Maturity SecuritiesEquity
Securities		Derivatives  
(In millions)Mortgage-
and
Asset-
Backed
Securities		Public
Utilities		Sovereign
and
Supranational		Banks/
Financial
Institutions		Other
Corporate		 Foreign
Currency
Swaps		Total
Balance, beginning of period$178 $224 $0 $23 $262 $80 $43 $810 
Net investment gains (losses) included
  in earnings		0 (1)0 0 0 16 (139)(124)
Unrealized gains (losses) included in
  other comprehensive income (loss)		9 19 0 0 12 0 (2)38 
Purchases, issuances, sales
  and settlements:
Purchases30 174 48 1 39 14 0 306 
Issuances0 0 0 0 0 0 0 0 
Sales0 0 0 0 0 (6)0 (6)
Settlements(2)(9)0 0 (1)0 0 (12)
Transfers into Level 39 15 0 0 2 0 0 26 
Transfers out of Level 30 0 0 0 (15)(2)0 (17)
Balance, end of period$224 $422 $48 $24 $299 $102 $(98)$1,021 
Changes in unrealized gains (losses)
  relating to Level 3 assets and liabilities
  still held at the end of the period
  included in earnings		$0 $0 $0 $0 $0 $0 $(139)$(139)
Level 3 Significant Unobservable Input Sensitivity

The following tables summarize the significant unobservable inputs used in the valuation of the Company's Level 3 investments and derivatives carried at fair value as of December 31. Included in the tables are the inputs or range of possible inputs that have an effect on the overall valuation of the financial instruments.
2021
(In millions)Fair ValueValuation Technique(s)Unobservable InputRange
(Weighted Average)
Assets:
  Securities available for sale, carried at fair value:
    Fixed maturity securities:
       Mortgage- and asset-backed securities$291 Consensus pricingOffered quotesN/A
(a)
       Public utilities493 Discounted cash flowCredit spreadsN/A
(a)
       Sovereign and supranational43 Discounted cash flowHistorical volatilityN/A
(a)
       Banks/financial institutions45 Consensus pricingOffered quotesN/A
(a)
       Other corporate426 Discounted cash flowCredit spreadsN/A
(a)
  Equity securities173 Net asset valueOffered quotesN/A
(a)
            Total assets$1,471 
(a) N/A represents securities where the Company receives unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs.
2020
(In millions)Fair ValueValuation Technique(s)Unobservable InputRange
(Weighted Average)
Assets:
  Securities available for sale, carried at fair value:
    Fixed maturity securities:
       Mortgage- and asset-backed securities$224 Consensus pricingOffered quotesN/A
(a)
       Public utilities422 Discounted cash flowCredit spreadsN/A
(a)
       Sovereign and supranational48 Discounted cash flowHistorical volatilityN/A
(a)
       Banks/financial institutions24 Consensus pricingOffered quotesN/A
(a)
       Other corporate299 Discounted cash flowCredit spreadsN/A
(a)
  Equity securities102 Net asset valueOffered quotesN/A
(a)
  Other assets:
       Foreign currency swaps69 Discounted cash flowInterest rates (USD).93%-1.40%
(b)
Interest rates (JPY).05%-.43%
(c)
CDS spreads22 bps-128 bps
64 Discounted cash flowInterest rates (USD).93%-1.40%
(b)
Interest rates (JPY).05%-.43%
(c)
            Total assets$1,252 
Liabilities:
  Other liabilities:
       Foreign currency swaps$160 Discounted cash flowInterest rates (USD).93%-1.12%
(b)
Interest rates (JPY).05%-.35%
(c)
CDS spreads41 bps-140 bps
71 Discounted cash flowInterest rates (USD).93%-1.12%
(b)
Interest rates (JPY).05%-.35%
(c)
            Total liabilities$231 
(a) N/A represents securities where the Company receives unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs.
(b) Inputs derived from U.S. long-term rates to accommodate long maturity nature of the Company's swaps
(c) Inputs derived from Japan long-term rates to accommodate long maturity nature of the Company's swaps
The following is a discussion of the significant unobservable inputs or valuation techniques used in determining the fair value of securities and derivatives classified as Level 3.

Net Asset Value

The Company holds certain unlisted equity securities whose fair value is derived based on the financial statements published by the investee. These securities do not trade on an active market and the valuations derived are dependent on the availability of timely financial reporting of the investee. Net asset value is an unobservable input in the determination of fair value of equity securities.

Offered Quotes

In circumstances where the Company's valuation model price is overridden because it implies a value that is not consistent with current market conditions, the Company will solicit bids from a limited number of brokers. The Company also receives unadjusted prices from brokers for its mortgage and asset-backed securities. These quotes are non-binding but are reflective of valuation best estimates at that particular point in time. Offered quotes are an unobservable input in the determination of fair value of mortgage- and asset-backed securities, certain banks/financial institutions, certain other corporate, and equity securities investments.

Interest Rates and CDS Spreads

The significant drivers of the valuation of the foreign exchange swaps are interest rates and CDS spreads. Some of the Company's swaps have long maturities that increase the sensitivity of the swaps to interest rate fluctuations. For the Company's foreign exchange or cross currency swaps that are in a net asset position, an increase in yen interest rates (all other factors held constant) will decrease the present value of the yen final settlement receivable (receive leg), thus decreasing the value of the swap as long as the derivative remains in a net asset position.
Foreign exchange swaps also have a lump-sum final settlement of foreign exchange principal amounts at the termination of the swap. Assuming all other factors are held constant, an increase in yen interest rates will decrease the receive leg and decrease the net value of the swap. Likewise, holding all other factors constant, an increase in U.S. dollar interest rates will increase the swap's net value due to the decrease in the present value of the dollar final settlement payable (pay leg).
The extinguisher feature in most of the Company's VIE swaps results in a cessation of cash flows and no further payments between the parties to the swap in the event of a default on the referenced or underlying collateral. To price this feature, the Company applies the survival probability of the referenced entity to the projected cash flows. The survival probability uses the CDS spreads and recovery rates to adjust the present value of the cash flows. For extinguisher swaps with positive values, an increase in CDS spreads decreases the likelihood of receiving the final exchange payments and reduces the value of the swap.

Effective October 1, 2021, the foreign exchange swaps mentioned above were transferred from level 3 to level 2 because the significant inputs used for their valuation that were previously unobservable are now observable.

For additional information on the Company's investments and financial instruments, see the accompanying Notes 1, 3 and 4.
v3.22.0.1
DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES
 12 Months Ended
Dec. 31, 2021
Deferred Policy Acquisition Costs Disclosures [Abstract]  
DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSESConsolidated policy acquisition costs deferred were $1.1 billion in 2021, compared with $1.2 billion in 2020 and $1.5 billion in 2019. The following table presents a rollforward of deferred policy acquisition costs by segment for the years ended December 31.
  20212020
(In millions)JapanU.S.JapanU.S.
Deferred policy acquisition costs:
Balance, beginning of year$6,991 $3,450 $6,584 $3,544 
Capitalization593 470 665 486 
Amortization(653)(517)(644)(570)
Foreign currency translation and other(698)(111)386 (10)
Balance, end of year$6,233 $3,292 $6,991 $3,450 
Commissions deferred as a percentage of total acquisition costs deferred were 71% in 2021, compared with 77% in 2020 and 74% in 2019.

Personnel, compensation and benefit expenses as a percentage of insurance expenses were 57% in 2021, compared with 59% in 2020 and 57% in 2019. Advertising expense, which is included in insurance expenses in the consolidated statements of earnings, was as follows for the years ended December 31:
(In millions)202120202019
Advertising expense:
Aflac Japan$91 $72 $101 
Aflac U.S.138 112 118 
          Total advertising expense$229 $184 $219 

Depreciation and other amortization expenses, which are included in insurance expenses in the consolidated statements of earnings, were as follows for the years ended December 31:
(In millions)202120202019
Depreciation expense$39 $36 $40 
Other amortization expense6 5 1 
          Total depreciation and other amortization expense$45 $41 $41 
v3.22.0.1
POLICY LIABILITIES
 12 Months Ended
Dec. 31, 2021
Insurance Loss Reserves [Abstract]  
POLICY LIABILITIES POLICY LIABILITIES
Policy liabilities consist of future policy benefits, unpaid policy claims, unearned premiums, and other policyholders' funds, which accounted for 86%, 5%, 2% and 7% of total policy liabilities at December 31, 2021, respectively. The Company regularly reviews the adequacy of its policy liabilities in total and by component.
The liability for future policy benefits as of December 31 consisted of the following:
  Liability AmountsInterest Rate Assumptions
(In millions)20212020
Health insurance
Japan$49,421 $54,659 
0.6 - 6.75
%
U.S.8,949 8,834 
3.0 - 8.0
Intercompany eliminations (1)
(456)(545)
2.0
Life insurance
Japan31,756 33,993 
0.6 - 4.5
U.S.918 842 
2.5 - 6.0
Total$90,588 $97,783 
(1) Elimination entry necessary due to recapture of a portion of policy liabilities ceded externally, as a result of the reinsurance retrocession transaction as described in Note 8 of the Notes to the Consolidated Financial Statements
The weighted-average interest rates reflected in the consolidated statements of earnings for future policy benefits for Japanese policies were 3.1% in 2021, compared with 3.1% in 2020 and 3.2% in 2019; and for U.S. policies, 5.1% in 2021, compared with 5.2% in 2020 and 5.3% in 2019.

Changes in the liability for unpaid policy claims were as follows for the years ended December 31:
(In millions)202120202019
Unpaid supplemental health claims, beginning of period$4,389 $3,968 $3,952 
Less reinsurance recoverables39 30 27 
Net balance, beginning of period4,350 3,938 3,925 
Add claims incurred during the period related to:
Current year6,969 7,179 7,216 
Prior years(860)(540)(552)
Total incurred6,109 6,639 6,664 
Less claims paid during the period on claims incurred during:
Current year4,356 4,488 4,715 
Prior years1,827 1,966 1,965 
Total paid6,183 6,454 6,680 
Effect of foreign exchange rate changes on unpaid claims(246)128 29 
Zurich acquisition0 99 0 
Net balance, end of period4,030 4,350 3,938 
Add reinsurance recoverables 37 39 30 
Unpaid supplemental health claims, end of period4,067 4,389 3,968 
Unpaid life claims, end of period769 798 691 
Total liability for unpaid policy claims$4,836 $5,187 $4,659 

The incurred claims development related to prior years reflects favorable claims experience compared to previous estimates. The favorable claims development of $860 million for 2021 comprises approximately $460 million from Japan and $400 million from the U.S., representing approximately 54% and 46% of the total, respectively. Excluding the impact of foreign exchange of a loss of approximately $35 million from December 31, 2020 to December 31, 2021, the favorable claims development in Japan would have been approximately $495 million, representing approximately 58% of the total.

The Company has experienced continued favorable claim trends in 2019, 2020, and 2021 for its core health products in Japan. During 2021 and 2020, there were impacts from lower utilization of healthcare services, due to the COVID-19 pandemic. This impacted both cancer and medical products, as the Japan population was avoiding doctor and hospital visits, and staying home more. This resulted in lower sickness, accident, and cancer incurred claims. In addition, dating back to before the pandemic, cancer treatment patterns in Japan are continuing to be influenced by significant advances in early-detection techniques and by the increased use of pathological diagnosis rather than clinical exams. Additionally, follow-up radiation and chemotherapy treatments are occurring more often on an outpatient basis. Such changes in treatment not only increase the quality of life and initial outcomes for the patients, but also decrease the average length of each hospital stay, resulting in favorable claims development.

In 2021, as experienced in 2020 and 2019, the majority of the Company's major U.S. accident and health lines of business, including accident, hospital indemnity, cancer, critical illness and short-term disability, the incurred claims development related to prior years reflects favorable claims experience compared to previous estimates. Continued general claim trends and refinements in estimates for COVID and non-COVID claims as experience emerged throughout the year also contributed to the favorable development in 2021.

As of December 31, 2021 and 2020, unearned premiums consisted primarily of discounted advance premiums on deposit. Discounted advance premiums are premiums on deposit from policyholders in conjunction with their purchase of certain Aflac Japan limited-pay insurance products. These advanced premiums are deferred upon collection and recognized as earned premiums over the contractual premium payment period. These advanced premiums represented 54% of the December 31, 2021 and 60% of the December 31, 2020 unearned premiums balances.

As of December 31, 2021 and 2020, the largest component of the other policyholders' funds liability was the Company's annuity line of business in Aflac Japan. The Company's annuities have fixed benefits and premiums. These annuities represented 97% of other policyholders' funds liability at December 31, 2021 and 2020.
v3.22.0.1
REINSURANCE
 12 Months Ended
Dec. 31, 2021
Reinsurance Disclosures [Abstract]  
REINSURANCE REINSURANCE
The Company periodically enters into fixed quota-share coinsurance agreements with other companies in the normal course of business. For each of its reinsurance agreements, the Company determines whether the agreement provides indemnification against loss or liability relating to insurance risk in accordance with applicable accounting standards. Reinsurance premiums and benefits paid or provided are accounted for on bases consistent with those used in accounting for the original policies issued and the terms of the reinsurance contracts. Premiums and benefits are reported net of insurance ceded.

The Company has recorded a deferred profit liability related to reinsurance transactions. The remaining deferred profit liability of $859 million, as of December 31, 2021, is included in future policy benefits in the consolidated balance sheet and is being amortized into income over the expected lives of the policies. The Company has also recorded a reinsurance recoverable for reinsurance transactions, which is included in other assets in the consolidated balance sheet and had a remaining balance of $937 million and $1.0 billion as of December 31, 2021 and 2020, respectively. The spot yen/dollar exchange rate weakened by approximately 10.0% and ceded reserves increased approximately 9.6% from December 31, 2020 to December 31, 2021.

The following table reconciles direct premiums and direct benefits and claims to net amounts after the effect of reinsurance which also includes the elimination of inter-segment amounts associated with affiliated reinsurance for the years ended December 31.
(In millions)202120202019
Direct earned premiums$17,857 $18,955 $19,122 
Ceded to other companies:
    Ceded Aflac Japan closed blocks(431)(466)(478)
    Other(73)(87)(69)
Assumed from other companies:
    Retrocession activities180 195 200 
    Other114 25 5 
Net earned premiums$17,647 $18,622 $18,780 
Direct benefits and claims$10,716 $12,080 $12,237 
Ceded benefits and change in reserves for future benefits:
    Ceded Aflac Japan closed blocks(379)(419)(433)
    Eliminations31 39 41 
    Other(36)(63)(57)
Assumed from other companies:
    Retrocession activities165 180 194 
    Eliminations(31)(39)(41)
    Other110 18 1 
Benefits and claims, net$10,576 $11,796 $11,942 

These reinsurance transactions are indemnity reinsurance that do not relieve the Company from its obligations to policyholders. In the event that the reinsurer is unable to meet their obligations, the Company remains liable for the reinsured claims.

As a part of its capital contingency plan, the Company entered into a committed reinsurance facility agreement on December 1, 2015, with reserves of approximately ¥120 billion as of December 31, 2021. This reinsurance facility agreement was renewed in 2021 and is effective until December 31, 2022. There are also additional commitment periods of a one-year duration each of which are automatically extended unless notification is received from the reinsurer within 60 days prior to the expiration. The reinsurer can withdraw from the committed facility if Aflac‘s Standard and Poor's (S&P) rating drops below BBB-. As of December 31, 2021, the Company had not executed a reinsurance treaty under this committed reinsurance facility.
v3.22.0.1
NOTES PAYABLE AND LEASE OBLIGATIONS
 12 Months Ended
Dec. 31, 2021
Debt Disclosure [Abstract]  
NOTES PAYABLE AND LEASE OBLIGATIONS NOTES PAYABLE AND LEASE OBLIGATIONS
A summary of notes payable and lease obligations as of December 31 follows:
(In millions)20212020
3.625% senior notes paid May 2021
$0 $698 
3.625% senior notes due November 2024
748 747 
3.25% senior notes due March 2025
448 448 
1.125% senior sustainability notes due March 2026
397 0 
2.875% senior notes due October 2026
298 298 
3.60% senior notes due April 2030
991 990 
6.90% senior notes due December 2039
221 221 
6.45% senior notes due August 2040
255 254 
4.00% senior notes due October 2046
394 394 
4.750% senior notes due January 2049
541 541 
Yen-denominated senior notes and subordinated debentures:
.300% senior notes due September 2025 (principal amount ¥12.4 billion)
107 119 
.932% senior notes due January 2027 (principal amount ¥60.0 billion)
520 578 
.500% senior notes due December 2029 (principal amount ¥12.6 billion)
109 121 
.550% senior notes due March 2030 (principal amount ¥13.3 billion)
115 127 
1.159% senior notes due October 2030 (principal amount ¥29.3 billion)
254 282 
.633% senior notes due April 2031 (principal amount ¥30.0 billion)
259 0 
.843% senior notes due December 2031 (principal amount ¥9.3 billion)
81 90 
.750% senior notes due March 2032 (principal amount ¥20.7 billion)
179 198 
.844% senior notes due April 2033 (principal amount ¥12.0 billion)
104 0 
1.488% senior notes due October 2033 (principal amount ¥15.2 billion)
131 146 
.934% senior notes due December 2034 (principal amount ¥9.8 billion)
85 94 
.830% senior notes due March 2035 (principal amount ¥10.6 billion)
91 101 
1.039% senior notes due April 2036 (principal amount ¥10.0 billion)
86 0 
1.750% senior notes due October 2038 (principal amount ¥8.9 billion)
77 85 
1.122% senior notes due December 2039 (principal amount ¥6.3 billion)
54 61 
1.264% senior notes due April 2041 (principal amount ¥10.0 billion)
86 0 
2.108% subordinated debentures due October 2047 (principal amount ¥60.0 billion)
517 575 
.963% subordinated bonds due April 2049 (principal amount ¥30.0 billion)
260 289 
1.560% senior notes due April 2051 (principal amount ¥20.0 billion)
172 0 
Yen-denominated loans:
Variable interest rate loan due September 2026 (.41% in 2021 and .43% in 2020,
  principal amount ¥5.0 billion)
43 48 
Variable interest rate loan due September 2029 (.56% in 2021 and .58% in 2020,
  principal amount ¥25.0 billion)
216 240 
Finance lease obligations payable through 202712 11 
Operating lease obligations payable through 2049105 143 
Total notes payable and lease obligations$7,956 $7,899 
Amounts in the table above are reported net of debt issuance costs and issuance premiums or discounts, if applicable, that are being amortized over the life of the notes.
In April 2021, the Parent Company issued five series of senior notes totaling ¥82.0 billion through a public debt offering under its then existing U.S. shelf registration statement. The first series, which totaled ¥30.0 billion, bears interest at a fixed rate of .633% per annum, payable semi-annually, and will mature in April 2031. The second series, which totaled ¥12.0 billion, bears interest at a fixed rate of .844% per annum, payable semi-annually, and will mature in April 2033. The third series, which totaled ¥10.0 billion, bears interest at a fixed rate of 1.039% per annum, payable semi-annually, and will mature in April 2036. The fourth series, which totaled ¥10.0 billion, bears interest at a fixed rate of 1.264% per annum, payable semi-annually, and will mature in April 2041. The fifth series, which totaled ¥20.0 billion, bears interest at a fixed rate of 1.560% per annum, payable semi-annually, and will mature in April 2051. The notes are redeemable at the Parent Company’s option (i) at any time, in whole but not in part, upon the occurrence of certain changes affecting U.S. taxation, as specified in the indenture governing the terms of the issuance or (ii) on or after the date that is six months prior to the stated maturity date of the series, in whole or in part, at a redemption price equal to the aggregate principal amount to be redeemed plus accrued and unpaid interest on the principal amount to be redeemed to, but excluding, the date of redemption.

In March 2021, the Parent Company issued $400 million of senior sustainability notes through a U.S. public debt offering. The notes bear interest at a fixed rate of 1.125% per annum, payable semi-annually, and will mature in March 2026. The Company intends, but is not contractually committed, to allocate an amount at least equivalent to the net proceeds from this issuance exclusively to existing or future investments in, or financing of, assets, businesses or projects that meet the eligibility criteria of the Company's sustainability bond framework described in the offering documentation in connection with such notes. These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 10 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.

In April 2020, the Parent Company issued $1.0 billion of senior notes through a U.S. public debt offering. The notes bear interest at a fixed rate of 3.60% per annum, payable semi-annually, and will mature in April 2030. These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 45 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.

In March 2020, the Parent Company issued four series of senior notes totaling ¥57.0 billion through a public debt offering under its U.S. shelf registration statement. The first series, which totaled ¥12.4 billion, bears interest at a fixed rate of .300% per annum, payable semi-annually and will mature in September 2025. The second series, which totaled ¥13.3 billion, bears interest at a fixed rate of .550% per annum, payable semi-annually, and will mature in March 2030. The third series, which totaled ¥20.7 billion, bears interest at a fixed rate of .750% per annum, payable semi-annually and will mature in March 2032. The fourth series, which totaled ¥10.6 billion, bears interest at a fixed rate of .830% per annum, payable semi-annually, and will mature in March 2035. These notes may only be redeemed before maturity, in whole but not in part, upon the occurrence of certain changes affecting U.S. taxation, as specified in the indenture governing the terms of the issuance.

In December 2019, the Parent Company issued four series of senior notes totaling ¥38.0 billion through a public debt offering under its U.S. shelf registration statement. The first series, which totaled ¥12.6 billion, bears interest at a fixed rate of .500% per annum, payable semi-annually, and will mature in December 2029. The second series, which totaled ¥9.3 billion, bears interest at a fixed rate of .843% per annum, payable semi-annually, and will mature in December 2031. The third series, which totaled ¥9.8 billion, bears interest at a fixed rate of .934% per annum, payable semi-annually, and will mature in December 2034. The fourth series, which totaled ¥6.3 billion, bears interest at a fixed rate of 1.122% per annum, payable semi-annually, and will mature in December 2039. These notes may only be redeemed before maturity, in whole but not in part, upon the occurrence of certain changes affecting U.S. taxation, as specified in the indenture governing the terms of the issuance.

In September 2019, the Parent Company renewed a ¥30.0 billion senior term loan facility. The first tranche of the facility, which totaled ¥5.0 billion, bears interest at a rate per annum equal to the Tokyo interbank market rate (TIBOR), or alternate TIBOR, if applicable, plus the applicable TIBOR margin and will mature in September 2026. The applicable
margin ranges between .30% and .70%, depending on the Parent Company's debt ratings as of the date of determination. The second tranche, which totaled ¥25.0 billion, bears interest at a rate per annum equal to the TIBOR, or alternate TIBOR, if applicable, plus the applicable TIBOR margin and will mature in September 2029. The applicable margin ranges between .45% and 1.00%, depending on the Parent Company's debt ratings as of the date of determination.

In April 2019, ALIJ issued ¥30.0 billion (par value) of perpetual subordinated bonds. These bonds bear interest at a fixed rate of .963% per annum and then at six-month Euro Yen LIBOR plus an applicable spread on and after the day immediately following April 18, 2024. The bonds will be callable on each interest payment date on and after April 18, 2024. In November 2019, ALIJ amended the bonds to change their duration from perpetual to a stated maturity date of April 16, 2049 and to remove provisions that permitted ALIJ to defer payments of interest under certain circumstances.

In October 2018, the Parent Company issued $550 million of senior notes through a U.S. public debt offering. The notes bear interest at a fixed rate of 4.750% per annum, payable semi-annually, and will mature in January 2049. These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 25 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.

In October 2018, the Parent Company issued three series of senior notes totaling ¥53.4 billion through a public debt offering under its U.S. shelf registration statement. The first series, which totaled ¥29.3 billion, bears interest at a fixed rate of 1.159% per annum, payable semi-annually, and will mature in October 2030. The second series, which totaled ¥15.2 billion, bears interest at a fixed rate of 1.488% per annum, payable semi-annually, and will mature in October 2033. The third series, which totaled ¥8.9 billion, bears interest at a fixed rate of 1.750% per annum, payable semi-annually, and will mature in October 2038. These notes may only be redeemed before maturity, in whole but not in part, upon the occurrence of certain changes affecting U.S. taxation, as specified in the indenture governing the terms of the issuance.

In October 2017, the Parent Company issued ¥60.0 billion of subordinated debentures through a U.S. public debt offering. The debentures bear interest at an initial rate of 2.108% per annum through October 22, 2027, or earlier redemption. Thereafter, the rate of the interest of the debentures will be reset every five years at a rate of interest equal to the then-current JPY 5-year Swap Offered Rate plus 205 basis points. The debentures are payable semi-annually in arrears and will mature in October 2047. The debentures are redeemable (i) at any time, in whole but not in part, upon the occurrence of certain tax events or certain rating agency events, as specified in the indenture governing the terms of the debentures or (ii) on or after October 23, 2027, in whole or in part, at a redemption price equal to their principal amount plus accrued and unpaid interest to, but excluding, the date of redemption.

In January 2017, the Parent Company issued ¥60.0 billion of senior notes through a U.S. public debt offering. The notes bear interest at a fixed rate of .932% per annum, payable semi-annually, and will mature in January 2027. These notes may only be redeemed before maturity, in whole but not in part, upon the occurrence of certain changes affecting U.S. taxation, as specified in the indenture governing the terms of the issuance.

In September 2016, the Parent Company issued two series of senior notes totaling $700 million through a U.S. public debt offering. The first series, which totaled $300 million, bears interest at a fixed rate of 2.875% per annum, payable semi-annually and will mature in October 2026. The second series, which totaled $400 million, bears interest at a fixed rate of 4.00% per annum, payable semi-annually, and will mature in October 2046.

In March 2015, the Parent Company issued $450 million of senior notes through a U.S. public debt offering. The notes bear interest at a fixed rate of 3.25% per annum, payable semi-annually, and will mature in March 2025. The Parent Company entered into cross-currency swaps that convert the U.S. dollar-denominated principal and interest on the senior notes into yen-denominated obligations which results in lower nominal net interest rates on the debt. By entering into these cross-currency swaps, the Parent Company economically converted its $450 million liability into a ¥55.0 billion yen liability and reduced the interest rate on this debt from 3.25% in dollars to .82% in yen.

In November 2014, the Parent Company issued $750 million of senior notes through a U.S. public debt offering. The notes bear interest at a fixed rate of 3.625% per annum, payable semi-annually, and will mature in November 2024. These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not
including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the treasury rate plus 20 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date. The Parent Company entered into cross-currency interest rate swaps to reduce interest expense by converting the U.S. dollar-denominated principal and interest on the senior notes it issued into yen-denominated obligations. By entering into the swaps, the Parent Company economically converted its $750 million liability into an ¥85.3 billion liability and reduced the interest rate on this debt from 3.625% in dollars to 1.00% in yen.

In June 2013, the Parent Company issued $700 million of senior notes through a U.S. public debt offering. The notes bear interest at a fixed rate of 3.625% per annum, payable semi-annually, and will mature in June 2023. These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the treasury rate plus 20 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date. The Parent Company entered into cross-currency interest rate swaps to reduce interest expense by converting the U.S. dollar-denominated principal and interest on the senior notes it issued into yen-denominated obligations. By entering into these swaps, the Parent Company economically converted its $700 million liability into a ¥69.8 billion liability and reduced the interest rate on this debt from 3.625% in dollars to 1.50% in yen. In May 2021, the Parent Company used a portion of the net proceeds from the April 2021 issuance of its various series of senior notes to redeem $700 million of its 3.625% senior notes due June 2023.

In 2010 and 2009, the Parent Company issued senior notes through U.S. public debt offerings; the details of these notes are as follows. In August 2010, the Parent Company issued $450 million of senior notes that will mature in August 2040. In December 2009, the Parent Company issued $400 million of senior notes that will mature in December 2039. These senior notes pay interest semiannually and are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the principal amount of the notes or (ii) the present value of the remaining scheduled payments of principal and interest to be redeemed, discounted to the redemption date, plus accrued and unpaid interest. In December 2016, the Parent Company completed a tender offer in which it extinguished $176 million principal of its 6.90% senior notes due December 2039 and $193 million principal of its 6.45% senior notes due August 2040. The pretax loss due to the early redemption of these notes was $137 million.

For the Company's yen-denominated notes and loans, the principal amount as stated in dollar terms will fluctuate from period to period due to changes in the yen/dollar exchange rate. The Company has designated the majority of its yen-denominated notes payable as a nonderivative hedge of the foreign currency exposure of the Company's investment in Aflac Japan.

The aggregate contractual maturities of notes payable during each of the years after December 31, 2021, are as follows:
(In millions)Total
Notes
Payable
2022$0 
20230 
2024750 
2025558 
2026743 
Thereafter5,847 
Total$7,898 
The following table presents the contractual maturities and present value of lease liabilities as of December 31, 2021.
(In millions)Operating LeasesFinance LeasesTotal
2022$48 $4 $52 
202316 3 19 
202411 3 14 
202511 2 13 
20268 0 8 
Thereafter17 0 17 
Total lease payments$111 $12 $123 
Less: Interest6 0 6 
Present value of lease liabilities$105 $12 $117 

The following table presents the weighted average remaining lease term and weighted average discount rate for lease liabilities as of December 31.
20212020
Weighted average remaining lease term (years):
Operating leases6.86.7
Finance leases3.53.5
Weighted average discount rate:
Operating leases2.2%2.0%
Finance leases1.4%1.5%

Operating lease costs, included in insurance expenses in the consolidated statements of earnings, were $58 million, $56 million and $54 million for the years ended December 31, 2021, 2020 and 2019, respectively. Operating cash outflows for operating leases were $56 million, $54 million and $52 million for the years ended December 31, 2021, 2020 and 2019, respectively.
A summary of the Company's lines of credit as of December 31, 2021 follows:
BorrowerTypeOriginal TermExpiration DateCapacityAmount OutstandingInterest Rate on Borrowed AmountMaturity PeriodCommitment FeeBusiness Purpose
Aflac Incorporated
and Aflac		uncommitted bilateral364 daysDecember 30, 2022
$100 million
$0 million
The rate quoted by the bank and agreed upon at the time of borrowing
Up to 3 months
NoneGeneral corporate purposes
Aflac Incorporatedunsecured revolving5 yearsMarch 29,
2024, or the date commitments are terminated pursuant to an event of default
¥100.0 billion
¥0.0 billion
A rate per annum equal to (a) Tokyo interbank market rate (TIBOR) plus, the alternative applicable TIBOR margin during the availability period from the closing date to the commitment termination date or (b) the TIBOR rate offered by the agent to major banks in yen for the applicable period plus, the applicable alternative TIBOR margin during the term out periodNo later than
March 29, 2024
.30% to .50%, depending on the Parent Company's debt ratings as of the date of determination
General corporate purposes, including a capital contingency plan for the operations of the Parent Company
Aflac Incorporated
and Aflac		unsecured revolving5 yearsNovember 18, 2024, or the date commitments are terminated pursuant to an event of default
$1.0 billion
$0.0 billion
A rate per annum equal to, at the Company's option, either, (a) USD LIBOR for U.S. dollar denominated borrowings or TIBOR for Japanese yen denominated borrowings, in either case adjusted for certain costs or (b) a base rate determined by reference to the highest of (1) the federal funds rate plus 1/2 of 1%, (2) the rate of interest for such day announced by Mizuho Bank, Ltd. as its prime rate, or (3) the eurocurrency rate for an interest period of one month plus 1.00%, in each case plus an applicable marginNo later than November 18, 2024
.085% to
.225%, depending on the Parent Company's debt ratings as of the date of determination
General corporate purposes, including a capital contingency plan for the operations of the Parent Company
Aflac Incorporated
and Aflac		uncommitted bilateralNone specifiedNone specified
$50 million
$0 million
A rate per annum equal to, at the Parent Company's option, either (a) a rate determined by reference to USD LIBOR for the interest period relevant to such borrowing or (b) the base rate determined by reference to the highest of (a) the lender's U.S. dollar short-term commercial loan rate, (b) the federal funds rate plus 1/2 of 1% and (c) USD one-month LIBOR plus 1%. USD LIBOR is subject to replacement with Secured Overnight Financing Rate (SOFR) under certain circumstances
Up to 3 months
NoneGeneral corporate purposes
Aflac(1)
uncommitted revolving364 daysNovember 30, 2022
$250 million
$0 million
USD three-month LIBOR plus 75 basis points per annum
3 months
NoneGeneral corporate purposes
Aflac Incorporated(1)
(Tranche 1)
uncommitted revolving364 daysNovember 25, 2022
¥50.0 billion
¥0.0 billion
Three-month TIBOR plus 70 basis points per annum
3 months
NoneGeneral corporate purposes
Aflac Incorporated(1)
(Tranche 2)
uncommitted revolving364 daysNovember 25, 2022
¥50.0 billion
¥0.0 billion
Three-month TIBOR plus 70 basis points per annum
3 months
NoneGeneral corporate purposes
Aflac New York(1)
uncommitted revolving364 daysApril 8, 2022
$25 million
$0 million
USD three-month LIBOR plus 75 basis points per annum
3 months
NoneGeneral corporate purposes
CAIC(1)
uncommitted revolving364 daysMarch 21, 2022
$15 million
$0 million
USD three-month LIBOR plus 75 basis points per annum
3 months
NoneGeneral corporate purposes
(1) Intercompany credit agreement
(continued)
BorrowerTypeOriginal TermExpiration DateCapacityAmount OutstandingInterest Rate on Borrowed AmountMaturity PeriodCommitment FeeBusiness Purpose
Tier One Insurance Company(1)
uncommitted revolving364 daysMarch 21, 2022
$0.3 million
$0 million
USD three-month LIBOR plus 75 basis points per annum
3 months
NoneGeneral corporate purposes
AGV Management Services Japan K.K.(1)
uncommitted revolving364 daysMay 2, 2022
¥500 million
¥350 million
A rate per annum equal to the short-term prime lending rates of banks appearing on the website for the Bank of Japan on the first day of the applicable periodNo later than
May 2, 2022		NoneGeneral corporate purposes
Hatch Healthcare
K.K.(1)
uncommitted revolving364 days
January 3, 2022(2)
¥900 million
¥0 million
A rate per annum equal to the short-term prime lending rates of banks appearing on the website for the Bank of Japan on the first day of the applicable periodNo later than January 3, 2022NoneGeneral corporate purposes
Hatch Insight K.K.(1)
uncommitted revolving364 days
January 3, 2022(2)
¥600 million
¥0 million
A rate per annum equal to the short-term prime lending rates of banks appearing on the website for the Bank of Japan on the first day of the applicable periodNo later than January 3, 2022NoneGeneral corporate purposes
Aflac GI Holdings LLC(1)
uncommitted revolving364 daysJuly 18, 2022
$30 million
$0 million
USD three-month LIBOR plus 75 basis points per annumNo later than
July 18, 2022		NoneGeneral corporate purposes
(1) Intercompany credit agreement
(2) Renewed in January 2022 with an expiration date of January 3, 2023
The Parent Company was in compliance with all of the covenants of its notes payable and lines of credit at December 31, 2021. No events of default or defaults occurred during 2021 and 2020.
v3.22.0.1
INCOME TAXES
 12 Months Ended
Dec. 31, 2021
Income Tax Disclosure [Abstract]  
INCOME TAXES INCOME TAXES
The components of income tax expense (benefit) applicable to pretax earnings for the years ended December 31 were as follows:
(In millions)ForeignU.S.Total
2021:
Current$884 $211 $1,095 
Deferred251 (349)(98)
Total income tax expense$1,135 $(138)$997 
2020:
Current$822 $(28)$794 
Deferred(28)(1,385)(1,413)
Total income tax expense$794 $(1,413)$(619)
2019:
Current$737 $69 $806 
Deferred183 152 335 
Total income tax expense$920 $221 $1,141 

The Japan income tax rate for the fiscal years 2021, 2020 and 2019 was 28.0%.

In March 2020, the Coronavirus Aid, Relief, and Economic Security (CARES) Act was signed into law and includes certain income tax provisions relevant to businesses. The Company was required to recognize the effect on the consolidated financial statements in the period the law was enacted, which was the period ended March 31, 2020. For the year ended December 31, 2020, the CARES Act did not have a material impact on the Company’s consolidated financial statements.
In September 2020, the U.S. Treasury and Internal Revenue Service issued Final and Proposed Regulations which address, among other items, the allocation of insurance expenses in the calculation of the foreign tax credit limitation. These regulations clarify how insurance related expenses are allocated and apportioned for this purpose. The Company had previously established valuation allowances on deferred foreign tax credits due to the uncertainty that previously existed. Under the guidance of these regulations, the Company recognized a one-time income tax benefit of $1.4 billion due to the release of these valuation allowances which were predominantly established on the Company’s deferred foreign tax credit benefits. The Company has determined that this will also reduce its effective tax rate in future periods, subject to any future changes in U.S. tax policy.

Income tax expense in the accompanying statements of earnings varies from the amount computed by applying the expected U.S. tax rate of 21% in 2021, 2020 and 2019 to pretax earnings. The principal reasons for the differences and the related tax effects for the years ended December 31 were as follows:
(In millions)202120202019
Income taxes based on U.S. statutory rates$1,118 $873 $933 
Foreign rate differential0 0 229 
Valuation allowance release0 (1,411)0 
Other, net(121)(81)(21)
Income tax expense$997 $(619)$1,141 
Total income tax expense for the years ended December 31 was allocated as follows:
(In millions)202120202019
Statements of earnings$997 $(619)$1,141 
Other comprehensive income (loss):
Unrealized foreign currency translation gains (losses) during
  period		15 (3)27 
Unrealized gains (losses) on fixed maturity securities:
Unrealized holding gains (losses) on fixed maturity
  securities during period		(194)223 1,532 
Reclassification adjustment for (gains) losses
  on fixed maturity securities included in net earnings		(7)33 5 
Unrealized gains (losses) on derivatives during period1 0 (3)
Pension liability adjustment during period30 (2)(18)
Total income tax expense (benefit) related to items of
  other comprehensive income (loss)		(155)251 1,543 
Total income taxes$842 $(368)$2,684 

The income tax effects of the temporary differences that gave rise to deferred income tax assets and liabilities as of December 31 were as follows:
(In millions)20212020
Deferred income tax liabilities:
Deferred policy acquisition costs$3,262 $3,663 
Unrealized gains and other basis differences on investments5,313 5,227 
Foreign currency gain on Aflac Japan0 70 
Premiums receivable66 112 
Policy benefit reserves3,578 3,834 
Total deferred income tax liabilities12,219 12,906 
Deferred income tax assets:
Unfunded retirement benefits7 9 
Other accrued expenses38 37 
Policy and contract claims794 868 
Foreign currency loss on Aflac Japan91 0 
Deferred compensation104 137 
Capital loss carryforwards0 12 
Depreciation230 202 
Anticipatory foreign tax credit5,883 5,972 
Deferred foreign tax credit701 647 
Other163 326 
Total deferred income tax assets8,011 8,210 
Net deferred income tax liability4,208 4,696 
Current income tax (asset) liability131 (35)
Total income tax liability$4,339 $4,661 

The application of U.S. GAAP requires the Company to evaluate the recoverability of deferred tax assets and establish a valuation allowance if necessary to reduce the deferred tax asset to an amount that is more likely than not expected to be realized. The Company has determined no valuation allowance against its anticipatory foreign tax credits is necessary. The anticipatory foreign tax credit represents the foreign tax credit the Company will generate from the reversal of Japan deferred tax liabilities in the future. The release of the valuation allowance on the anticipatory foreign tax credit is due to the regulations addressing the allocation of insurance expenses in the calculation of the foreign tax credit released September 29, 2020. The Company has also determined no valuation allowance against its deferred foreign tax credits is necessary. Deferred foreign tax credits are foreign tax credits generated in the current tax year by the Japanese life company, but are unable to be utilized until 2022 due to Japan's current tax year not closing until March 31, 2022. The
release of the valuation allowance on the deferred foreign tax credit is also due to the foreign tax credit regulations released September 29, 2020. Based upon a review of the Company's anticipated future taxable income, and including all other available evidence, both positive and negative, the Company's management has concluded that, notwithstanding the items noted above, it is more likely than not that all other deferred tax assets will be realized.

Under U.S. income tax rules, only 35% of non-life operating losses can be offset against life insurance taxable income each year. For current U.S. income tax purposes, as of December 31, 2021, there were non-life operating loss carryforwards of $56 million available to offset against future taxable income, all of which do not expire. The Company has no capital loss carryforwards available to offset capital gains. The Company has foreign tax credit carryforwards of $31 million available to offset against future excess foreign taxes paid, $3 million of which expire in 2030 with the remaining $28 million expiring in 2031.

The Company files federal income tax returns in the U.S. and Japan as well as state or prefecture income tax returns in various jurisdictions in the two countries. There are currently no open Federal, State, or local U.S. income tax audits. U.S. federal income tax returns for years before 2016 are no longer subject to examination. Japan corporate income tax returns for years before 2016 are no longer subject to examination. Management believes it has established adequate tax liabilities and final resolution of all open audits is not expected to have a material impact on the Company's consolidated financial statements.

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows for the years ended December 31:
(In millions)2021 2020 
Balance, beginning of year$19 $17 
Additions for tax positions of prior years1   2   
Reductions for tax positions of prior years(15)  0 
Balance, end of year$5 $19 

Included in the balance of the liability for unrecognized tax benefits at December 31, 2021, are no tax positions for which the ultimate deductibility is highly certain, but for which there is uncertainty about the timing of such deductibility, compared with $15 million at December 31, 2020. Because of the impact of deferred tax accounting, other than interest and penalties, the disallowance of the shorter deductibility period would not affect the annual effective tax rate, but would accelerate the payment of cash to the taxing authority to an earlier period. The Company has accrued approximately $5 million as of December 31, 2021, for permanent uncertainties, which if reversed would not have a material effect on the annual effective rate.

The Company recognizes accrued interest and penalties related to unrecognized tax benefits in income tax expense. The Company recognized approximately $1 million in interest and penalties in 2021, 2020 and 2019, respectively. The Company accrued an immaterial amount for the payment of interest and penalties as of December 31, 2021, compared with $3 million at December 31, 2020.

As of December 31, 2021, there were no material uncertain tax positions for which the total amounts of unrecognized tax benefits will significantly increase or decrease within the next 12 months.
v3.22.0.1
SHAREHOLDERS' EQUITY
 12 Months Ended
Dec. 31, 2021
Stockholders' Equity Note [Abstract]  
SHAREHOLDERS' EQUITY SHAREHOLDERS' EQUITYThe following table is a reconciliation of the number of shares of the Company's common stock for the years ended December 31.
(In thousands of shares)202120202019
Common stock - issued:
Balance, beginning of period1,351,0181,349,3091,347,540
Exercise of stock options and issuance of restricted shares1,7211,7091,769
Balance, end of period1,352,7391,351,0181,349,309
Treasury stock:
Balance, beginning of period658,564622,516592,254
Purchases of treasury stock:
Share repurchase program43,32737,89931,994
Other437542592
Dispositions of treasury stock:
Shares issued to AFL Stock Plan(1,216)(2,021)(1,610)
Exercise of stock options(275)(121)(418)
Other(230)(251)(296)
Balance, end of period700,607658,564622,516
Shares outstanding, end of period652,132692,454726,793

Outstanding share-based awards are excluded from the calculation of weighted-average shares used in the computation of basic EPS. The following table presents the approximate number of share-based awards to purchase shares, on a weighted-average basis, that were considered to be anti-dilutive and were excluded from the calculation of diluted EPS at December 31:
(In thousands)202120202019
Anti-dilutive share-based awards0 687 6 

The weighted-average shares used in calculating EPS for the years ended December 31 were as follows: 
(In thousands of shares)202120202019
Weighted-average outstanding shares used for calculating basic EPS673,617 713,702 742,414 
Dilutive effect of share-based awards3,112 2,490 4,016 
Weighted-average outstanding shares used for calculating diluted EPS676,729 716,192 746,430 

Share Repurchase Program: During 2021, the Company repurchased 43.3 million shares of its common stock in the open market for $2.3 billion. The Company repurchased 37.9 million shares for $1.5 billion in 2020 and 32.0 million shares for $1.6 billion in 2019. In August 2020, the Company's board of directors authorized the purchase of an additional 100 million shares of its common stock. As of December 31, 2021, a remaining balance of 55.8 million shares of the Company's common stock was available for purchase under share repurchase authorizations by its board of directors.

Voting Rights: In accordance with the Parent Company's articles of incorporation, shares of common stock are generally entitled to one vote per share until they have been held by the same beneficial owner for a continuous period of 48 months, at which time they become entitled to 10 votes per share.
Reclassifications from Accumulated Other Comprehensive Income
The tables below are reconciliations of accumulated other comprehensive income by component for the years ended December 31.
Changes in Accumulated Other Comprehensive Income
2021
(In millions)Unrealized Foreign
Currency Translation
Gains (Losses)		Unrealized
Gains (Losses)
on Fixed Maturity Securities		Unrealized
Gains (Losses)
on Derivatives		Pension
Liability
Adjustment		Total
Balance at December 31, 2020$(1,109)$10,361 $(34)$(284)$8,934 
Other comprehensive
   income (loss) before
   reclassification 		(904)(735)(1)90 (1,550)
Amounts reclassified from
   accumulated other
   comprehensive income
  (loss)		0 (24)5 28 9 
Net current-period other
   comprehensive
   income (loss)		(904)(759)4 118 (1,541)
Balance at December 31, 2021$(2,013)$9,602 $(30)$(166)$7,393 
All amounts in the table above are net of tax.
2020
(In millions)Unrealized Foreign
Currency Translation
Gains (Losses)		Unrealized
Gains (Losses)
on Fixed Maturity Securities		Unrealized
Gains (Losses)
on Derivatives		Pension Liability AdjustmentTotal
Balance at December 31, 2019$(1,623)$8,548 $(33)$(277)$6,615 
Cumulative effect of change
   in accounting principle -
   ASU 2019-04		0 848 0 0 848 
Balance at January 1, 2020$(1,623)$9,396 $(33)$(277)$7,463 
Other comprehensive
   income (loss) before
   reclassification		514 839 (1)(30)1,322 
Amounts reclassified from
   accumulated other
   comprehensive income
  (loss)		0 126 0 23 149 
Net current-period other
   comprehensive
   income (loss)		514 965 (1)(7)1,471 
Balance at December 31, 2020$(1,109)$10,361 $(34)$(284)$8,934 
All amounts in the table above are net of tax.
2019
(In millions)Unrealized Foreign
Currency Translation
Gains (Losses)		Unrealized
Gains (Losses)
on Fixed Maturity Securities		Unrealized
Gains (Losses)
on Derivatives		Pension Liability AdjustmentTotal
Balance at December 31, 2018$(1,847)$4,234 $(24)$(212)$2,151 
Other comprehensive
   income (loss) before
   reclassification		224 4,327 (9)(76)4,466 
Amounts reclassified from
   accumulated other
   comprehensive income
  (loss)		0 (13)0 11 (2)
Net current-period other
   comprehensive
   income (loss)		224 4,314 (9)(65)4,464 
Balance at December 31, 2019$(1,623)$8,548 $(33)$(277)$6,615 
All amounts in the table above are net of tax.
The tables below summarize the amounts reclassified from each component of accumulated other comprehensive income based on source for the years ended December 31.

Reclassifications Out of Accumulated Other Comprehensive Income
(In millions)2021
Details about Accumulated Other Comprehensive Income ComponentsAmount Reclassified from Accumulated Other Comprehensive IncomeAffected Line Item in the
Statements of Earnings
Unrealized gains (losses) on available-for-sale
   securities		$31 Net investment gains (losses)
(7)
Tax (expense) or benefit(1)
$24 Net of tax
Unrealized gains (losses) on derivatives$(5)Net investment gains (losses)
(1)Net investment income
(6)Total before tax
1 
Tax (expense) or benefit(1)
$(5)Net of tax
Amortization of defined benefit pension items:
       Actuarial gains (losses)$(35)
Acquisition and operating expenses(2)
Prior service (cost) credit0 
Acquisition and operating expenses(2)
7 
Tax (expense) or benefit(1)
$(28)Net of tax
Total reclassifications for the period$(9)Net of tax
(1) Based on 21% tax rate
(2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 14 for additional details).
(In millions)2020
Details about Accumulated Other Comprehensive Income ComponentsAmount Reclassified from Accumulated Other Comprehensive IncomeAffected Line Item in the
Statements of Earnings
Unrealized gains (losses) on available-for-sale
   securities		$(159)Net investment gains (losses)
33 
Tax (expense) or benefit(1)
$(126)Net of tax
Amortization of defined benefit pension items:
       Actuarial gains (losses)$(32)
Acquisition and operating expenses(2)
Prior service (cost) credit3 
Acquisition and operating expenses(2)
6 
Tax (expense) or benefit(1)
$(23)Net of tax
Total reclassifications for the period$(149)Net of tax
(1) Based on 21% tax rate
(2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 14 for additional details).

(In millions)2019
Details about Accumulated Other Comprehensive Income ComponentsAmount Reclassified from Accumulated Other Comprehensive IncomeAffected Line Item in the
Statements of Earnings
Unrealized gains (losses) on available-for-sale
   securities		$18 Net investment gains (losses)
(5)
Tax (expense) or benefit(1)
$13 Net of tax
Amortization of defined benefit pension items:
       Actuarial gains (losses)$(15)
Acquisition and operating expenses(2)
       Prior service (cost) credit0 
Acquisition and operating expenses(2)
4 
Tax (expense) or benefit(1)
$(11)Net of tax
Total reclassifications for the period$2 Net of tax
(1) Based on 26% blended tax rate
(2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 14 for additional details).
v3.22.0.1
SHARE-BASED COMPENSATION
 12 Months Ended
Dec. 31, 2021
Share-based Payment Arrangement [Abstract]  
SHARE-BASED COMPENSATION SHARE-BASED COMPENSATION
As of December 31, 2021, the Company has outstanding share-based awards under the Aflac Incorporated Long-Term Incentive Plan (the Plan). Share-based awards are designed to reward employees for their long-term contributions to the Company and provide incentives for them to remain with the Company. The number and frequency of share-based awards are based on competitive practices, operating results of the Company, government regulations, and other factors.
In June 2020, the Company transitioned from E*Trade Financial Corporate Services, Inc. to Fidelity Management Trust Company as the trustee and recordkeeper of the Company's long-term share-based compensation plans.
The Plan, as amended on February 14, 2017, allows for a maximum number of shares issuable over its term of 75 million shares including 38 million shares that may be awarded in respect of awards other than options or stock appreciation rights. If any awards granted under the Plan are forfeited or are terminated before being exercised or settled for any reason other than tax forfeiture, then the shares underlying the awards will again be available under the Plan.

The Plan allows awards to Company employees for incentive stock options (ISOs), non-qualifying stock options (NQSOs), restricted stock, restricted stock units, and stock appreciation rights. Non-employee directors are eligible for grants of NQSOs, restricted stock, and stock appreciation rights. As of December 31, 2021, approximately 36.7 million shares were available for future grants under this plan. The ISOs and NQSOs have a term of 10 years, and the share-based awards
generally vest upon time-based conditions or time and performance-based conditions. Time-based vesting generally occurs after three years. Performance-based vesting conditions generally include the attainment of goals related to Company financial performance. As of December 31, 2021, the only performance-based awards issued and outstanding were restricted stock awards and units.

Stock options and stock appreciation rights granted under the amended Plan have an exercise price of at least the fair market value of the underlying stock on the grant date and have an expiration date no later than 10 years from the grant date. Time-based restricted stock awards, restricted stock units and stock options granted after January 1, 2017 generally vest on a ratable basis over three years, and awards granted prior to the amendment vest on a three-year cliff basis. The Compensation Committee of the Board of Directors has the discretion to determine vesting schedules.

Share-based awards granted to U.S.-based grantees are settled with authorized but unissued Company stock, while those issued to Japan-based grantees are settled with treasury shares.
Summary of Share-Based Compensation Expense
Share-based compensation expense consists primarily of expenses for stock options, restricted stock awards (including performance based restricted stock awards), and restricted stock units granted to employees.
The following table presents the impact of the expense recognized in connection with share-based awards for the periods ended December 31.
(In millions, except for per-share amounts)202120202019
Impact on earnings from continuing operations$65 $61 $59 
Impact on earnings before income taxes65 61 59 
Impact on net earnings51 48 46 
Impact on net earnings per share:
Basic$.08 $.07 $.06 
Diluted.08 .07 .06 

Stock Options

The following table summarizes stock option activity under the employee stock option plan.
(In thousands of shares)Stock
Option
Shares		Weighted-Average
Exercise Price
Per Share
Outstanding at December 31, 20185,330 $28.54 
Granted in 20190 0.00 
Canceled in 2019(40)27.28 
Exercised in 2019(1,584)25.97 
Outstanding at December 31, 20193,706 29.65 
Granted in 202059 35.75 
Canceled in 2020(82)26.31 
Exercised in 2020(638)27.82 
Outstanding at December 31, 20203,045 30.25 
Granted in 20210 0.00 
Canceled in 2021(4)16.93 
Exercised in 2021(896)28.45 
Outstanding at December 31, 20212,145 $31.02 

(In thousands of shares)202120202019
Shares exercisable, end of year2,145 2,986 3,553 
The Company estimates the fair value of each stock option granted using the Black-Scholes-Merton multiple option approach. Expected volatility is based on historical periods generally commensurate with the estimated terms of the options. The Company uses historical data to estimate option exercise and termination patterns within the model. Separate groups of employees that have similar historical exercise patterns are stratified and considered separately for valuation purposes. The expected term of options granted is derived from the output of the Company's option model and represents the weighted-average period of time that options granted are expected to be outstanding. The Company bases the risk-free interest rate on the Treasury note rate with a term comparable to that of the estimated term of the options. There were no options granted in 2021 or 2019. The weighted-average fair value of options at their grant date was $6.33 in 2020. The following table presents the assumptions used in valuing options granted, if applicable, during the years ended December 31.
202120202019
Expected term (years)7.96.07.0
Expected volatility25.6 %24.4 %18.0 %
Annual forfeiture rate3.8 3.9 3.9 
Risk-free interest rate1.0 2.0 2.9 
Dividend yield3.0 3.3 2.2 

The following table summarizes information about stock options outstanding and exercisable at December 31, 2021.
(In thousands of shares)Options OutstandingOptions Exercisable
Range of
Exercise Prices
Per Share		Stock Option
Shares
Outstanding		Wgtd.-Avg.
Remaining
Contractual
Life (Yrs.)		Wgtd.-Avg.
Exercise
Price
Per Share		Stock Option
Shares
Exercisable		Wgtd.-Avg.
Exercise
Price
Per Share
$0.00 -$24.75 336 0.7$24.09 336 $24.09 
24.75 -28.97 370 3.928.85 370 28.85 
28.97 -31.21 718 2.830.74 718 30.74 
31.21 -36.21 572 4.734.36 572 34.36 
36.21 -44.59 149 5.840.57 149 40.57 
$0.00 -$44.59 2,145 3.4$31.02 2,145 $31.02 

The aggregate intrinsic value in the following table represents the total pretax intrinsic value, and is based on the difference between the exercise price of the stock options and the quoted closing common stock price of $58.39 as of December 31, 2021, for those awards that have an exercise price currently below the closing price. As of December 31, 2021, the aggregate intrinsic value of stock options outstanding was $59 million, with a weighted-average remaining term of 3.4 years. The total number of in-the-money stock options exercisable as of December 31, 2021, was 2.1 million shares. The aggregate intrinsic value of stock options exercisable at that same date was $59 million, with a weighted-average remaining term of 3.4 years.

The following table summarizes stock option activity during the years ended December 31.
(In millions)202120202019
Total intrinsic value of options exercised$21 $11 $38 
Cash received from options exercised26 18 40 
Tax benefit realized as a result of options exercised and
  restricted stock releases		17 18 34 

Performance-Based Restricted Stock Awards and Units

Under the Plan, the Company grants selected executive officers performance-based restricted stock awards (PBRS) each February whose vesting is contingent upon meeting various performance goals. PBRS are generally granted at-the-money and contingently cliff vest over a period of three years, generally subject to continued employment. In February 2021, the Company granted 454 thousand performance-based stock awards, which are contingent on the achievement of the Company's financial performance metrics and its market-based conditions. On the date of grant, the Company estimated the fair value of restricted stock awards with market-based conditions using a Monte Carlo simulation model.
The model discounts the value of the stock at the assumed vesting date based on a risk-free interest rate. Based on estimates of actual performance versus the vesting thresholds, the calculated fair value percentage pay-out estimate will be updated each quarter. Actual performance, including modification for relative total shareholder return, may result in the ultimate award of 0% to 200% percent of the initial number of PBRS issued, with the potential for no award if company performance goals are not achieved during the three-year period. PBRS subject to accelerated vesting at the date of retirement eligibility is recognized over the implicit service period.

The Company also granted selected executive officers performance-based restricted stock units (PSUs) throughout the year whose vesting is contingent upon meeting various performance goals. PSUs are generally granted at-the-money and contingently cliff vest over a period of three years, generally subject to continued employment. In 2021, the Company granted 26 thousand performance-based stock units, which are contingent on the achievement of certain Company determined metrics. Based on estimates of actual performance versus the vesting thresholds, the calculated fair value percentage pay-out estimate will be updated each quarter. Actual performance may result in the ultimate award of 0% to 200% percent of the initial number of PSUs issued, with the potential for no award if the Company determined metrics are not achieved during the three-year period. PSUs subject to accelerated vesting at the date of retirement eligibility is recognized over the implicit service period.

The Company uses third-party analyses to assist in developing the assumptions used in, as well as calibrating, a Monte Carlo simulation model. The Company is responsible for determining the assumptions used in estimating the fair value of its share-based payment awards.

Key assumptions used to value PBRS granted during 2021 follows:
(In millions)2021
Expected volatility (based on Aflac Inc. and peer group historical daily stock price) 36.75 %
Expected life from grant date (years)2.9
Risk-free interest rate (based on U.S. Treasury yields at the date of grant)0.18 %

Restricted Stock Awards and Units
The value of restricted stock awards and restricted stock units is based on the fair market value of the Company's common stock at the date of grant. The following table summarizes restricted stock activity during the years ended December 31. 
(In thousands of shares)SharesWeighted-Average
Grant-Date
Fair Value
Per  Share
Restricted stock at December 31, 20183,407 $36.52 
Granted in 2019 (1)
1,070 49.68 
Canceled in 2019 (1)
(39)41.60 
Vested in 2019 (1)
(1,723)32.50 
Restricted stock at December 31, 2019 (1)
2,715 43.74 
Granted in 20201,544 45.88 
Canceled in 2020(119)49.27 
Vested in 2020(1,560)35.23 
Restricted stock at December 31, 20202,580 48.57 
Granted in 20211,496 47.87 
Canceled in 2021(148)49.00 
Vested in 2021(1,371)45.80 
Restricted stock at December 31, 20212,557 $49.38 
(1) This balance has been adjusted to include dividends

As of December 31, 2021, total compensation cost not yet recognized in the Company's financial statements related to restricted stock awards and restricted stock units was $35 million, of which $13 million (1.2 million shares) was related to restricted stock awards with a performance-based vesting condition. The Company expects to recognize these amounts
over a weighted-average period of approximately 1.8 years. There are no other contractual terms covering restricted stock awards once vested.
v3.22.0.1
STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS
 12 Months Ended
Dec. 31, 2021
Insurance [Abstract]  
STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS
The Company's insurance subsidiaries are required to report their results of operations and financial position to insurance regulatory authorities on the basis of statutory accounting practices prescribed or permitted by such authorities.

Aflac Japan must report its results of operations and financial position to the Japanese Financial Services Agency (FSA) on a Japanese regulatory accounting basis as prescribed by the FSA. Japanese regulatory accounting practices differ in many respects from U.S. GAAP. Under Japanese regulatory accounting practices, policy acquisition costs are expensed immediately; policy benefit and claim reserving methods and assumptions are different; premiums are recognized on a cash basis; different consolidation criteria apply to VIEs; reinsurance is recognized on a different basis; and investments can have a separate accounting classification and treatment referred to as policy reserve matching bonds (PRM). Capital and surplus of Aflac Japan, based on Japanese regulatory accounting practices, was $9.8 billion at December 31, 2021, compared with $9.0 billion at December 31, 2020.

Aflac, CAIC and TOIC report statutory financial statements that are prepared on the basis of accounting practices prescribed or permitted by the Nebraska Department of Insurance (NDOI). The NDOI recognizes statutory accounting principles and practices prescribed or permitted by the state of Nebraska for determining and reporting the financial condition and results of operations of an insurance company, and for determining a company's solvency under Nebraska insurance law. 

Aflac New York reports statutory financial statements that are prepared on the basis of accounting practices prescribed or permitted by the New York State Department of Financial Services (NYDFS). The NYDFS recognizes statutory accounting principles and practices prescribed or permitted by the state of New York for determining and reporting the financial condition and results of operations of an insurance company, and for determining a company's solvency under New York insurance law.

Statutory Accounting Principles (SAP) as detailed by the National Association of Insurance Commissioners' (NAIC) Accounting Practices and Procedures Manual have been adopted by both the state of Nebraska and the state of New York as a component of those prescribed or permitted practices. Statutory accounting practices primarily differ from U.S. GAAP by charging policy acquisition costs to expense as incurred, establishing future policy benefit liabilities using different actuarial assumptions as well as valuing investments and certain assets and accounting for deferred taxes on a different basis. Additionally, the Director of the NDOI and the Superintendent of the NYDFS each have the right to permit other specific practices which deviate from prescribed practices. Aflac, CAIC, TOIC and Aflac New York had no permitted practices as of December 31, 2021 and 2020.

The table below represents statutory capital and surplus based on statutory accounting practices for the Company’s U.S. life insurance subsidiaries as of December 31.
(In millions)20212020
Aflac$2,627 $2,088 
CAIC244 271 
TOIC57 61 
Aflac New York360 352 

As of December 31, 2021, the capital and surplus for each of the Company's U.S. life insurance subsidiaries exceeded the required company action level capital and surplus.
The table below represents net income (loss) based on statutory accounting practices for the Company’s U.S. life insurance subsidiaries as of December 31.
(In millions)202120202019
Aflac$1,146 $872 $864 
CAIC(30)1 (16)
TOIC(27)(24)(2)
Aflac New York83 75 75 

The Parent Company depends on its subsidiaries for cash flow, primarily in the form of dividends and management fees. Consolidated retained earnings in the accompanying financial statements largely represent the undistributed earnings of the Company's insurance subsidiaries. Amounts available for dividends, management fees and other payments to the Parent Company by its insurance subsidiaries may fluctuate due to different accounting methods required by regulatory authorities. These payments are also subject to various regulatory restrictions and approvals related to safeguarding the interests of insurance policyholders. The Company's U.S. life insurance entities must maintain adequate risk-based capital (RBC) for U.S. regulatory authorities, and Aflac Japan must maintain adequate solvency margins for Japanese regulatory authorities.

The maximum amount of dividends that can be paid to the Parent Company by Aflac, CAIC and TOIC without prior approval of Nebraska's director of insurance is the greater of the net income from operations, which excludes net investment gains, for the previous year determined under statutory accounting principles, or 10% of statutory capital and surplus as of the previous year-end. In 2021, Aflac declared dividends of $654 million. Dividends declared by Aflac during 2022 in excess of $1.1 billion would require such approval. CAIC and TOIC did not declare dividends during 2021.

From time to time, Aflac New York pays dividends to Aflac, the parent company of Aflac New York. Aflac New York may not pay dividends to Aflac without the prior approval of the NYDFS. Aflac New York declared dividends of $75 million in 2021, which were authorized by the NYDFS.

Aflac Japan is required to meet certain financial criteria as governed by Japanese corporate law in order to provide dividends to the Parent Company. Under these criteria, dividend capacity at Aflac Japan is basically defined as retained earnings excluding capital reserves, which represent equity generated by capital profits that are statutorily required in Japan, less net after-tax unrealized losses on available-for-sale securities based on the previous fiscal year-end. Profits remitted by Aflac Japan to the Parent Company were as follows for the years ended December 31:
  
In DollarsIn Yen
(In millions of dollars and billions of yen)202120202019202120202019
Profit remittances$2,138 $1,215 $2,070 ¥236.7 ¥129.8 ¥225.2 
v3.22.0.1
BENEFIT PLANS
 12 Months Ended
Dec. 31, 2021
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]  
BENEFIT PLANS BENEFIT PLANS
Pension and Other Postretirement Plans
The Company has funded defined benefit plans in Japan and the U.S., however the U.S. plan was frozen to new participants effective October 1, 2013. The Company also maintains non-qualified, unfunded supplemental retirement plans that provide defined pension benefits in excess of limits imposed by federal tax law for certain Japanese, U.S. and former employees, however the U.S. plan was frozen to new participants effective January 1, 2015. U.S. employees who are not participants in the defined benefit plan receive a nonelective 401(k) employer contribution.

The Company provides certain health care benefits for eligible U.S. retired employees, their beneficiaries and covered dependents (other postretirement benefits). The health care plan is contributory and unfunded. Effective January 1, 2014, employees eligible for benefits included the following: (1) active employees whose age plus service, in years, equaled or exceeded 80 (rule of 80); (2) active employees who were age 55 or older and have met the 15 years of service requirement; (3) active employees who would meet the rule of 80 in the next five years; (4) active employees who were age 55 or older and who would meet the 15 years of service requirement within the next five years; and (5) current retirees. For certain employees and former employees, additional coverage is provided for all medical expenses for life.

Information with respect to the Company's benefit plans' assets and obligations as of December 31 was as follows:
Pension BenefitsOther
JapanU.S.Postretirement Benefits
(In millions)202120202021202020212020
Projected benefit obligation:
      Benefit obligation, beginning of year$473 $436 $1,204 $1,058 $42 $39 
      Service cost23 24 28 29 0 0 
      Interest cost6 5 32 34 1 1 
      Actuarial (gain) loss(9)(6)(50)106 (2)6 
      Benefits and expenses paid(15)(12)(28)(23)(5)(4)
      Effect of foreign exchange
         rate changes		(46)26 0 0 0 0 
               Benefit obligation, end of year432 473 1,186 1,204 36 42 
Plan assets:
      Fair value of plan assets,
         beginning of year		416 344 824 644 0 0 
      Actual return on plan assets14 21 81 96 0 0 
      Employer contributions44 41 8 107 5 4 
      Benefits and expenses paid(15)(12)(28)(23)(5)(4)
      Effect of foreign exchange
         rate changes		(44)22 0 0 0 0 
               Fair value of plan assets,
                  end of year		415 416 885 824 0 0 
Funded status of the plans(1)
$(17)$(57)$(301)$(380)$(36)$(42)
Amounts recognized in accumulated other
    comprehensive income:
      Net actuarial (gain) loss$50 $74 $158 $278 $10 $15 
      Prior service (credit) cost0 (1)(2)(2)0 0 
               Total included in accumulated
                  other comprehensive income		$50 $73 $156 $276 $10 $15 
Accumulated benefit obligation$346 $425 $1,010 $1,017   N/AN/A
(1) Recognized in other liabilities in the consolidated balance sheets
Information for Pension Plans with an Accumulated Benefit Obligation in Excess of Plan Assets
Pension Benefits
JapanU.S.
(In millions)2021202020212020
Accumulated benefit obligation $346 $425 $1,010 $1,017 
Fair value of plan assets415 416 885 824 
Information for Pension Plans with a Projected Benefit Obligation in Excess of Plan Assets
Pension Benefits
Japan (1)
U.S.(2)
(In millions)2021202020212020
Projected benefit obligation $432 $473 $1,186 $1,204 
Fair value of plan assets415 416 885 824 
(1) The net amount of projected benefit obligation and plan assets for the underfunded (including unfunded) Japan pension plan was $17 and $57 at December 31, 2021 and 2020, respectively, and was classified as liabilities on the statement of financial position.
(2) The net amount of projected benefit obligation and plan assets for the underfunded (including unfunded) U.S. pension plan was $301 and $380 at December 31, 2021 and 2020, respectively, and was classified as liabilities on the statement of financial position.

Information for other postretirement benefit plans with an accumulated postretirement benefit obligation in excess of plan assets has been disclosed in the note on “Obligations and Funded Status” because all the other postretirement benefit plans are unfunded or underfunded.
Pension BenefitsOther
JapanU.S.Postretirement Benefits
202120202019202120202019202120202019
Weighted-average
  actuarial assumptions:		                    
Discount rate - net periodic benefit cost.75%.75%1.25%2.68%3.25%4.25%2.68%3.25%4.25%
Discount rate - benefit
  obligations		.94.75.752.942.683.25  2.942.683.25  
Expected long-term return
  on plan assets		2.002.002.005.756.006.25N/AN/AN/A
Rate of compensation
  increase		N/AN/AN/A4.004.004.00N/AN/AN/A
Health care cost trend ratesN/AN/AN/AN/AN/AN/A5.80
(2)
6.30
(2)
7.50
(2)
(2) For the years 2021, 2020 and 2019, the health care cost trend rates are expected to trend down to 3.7% in 52 years, 3.7% in 53 years, and 3.8% in 54 years, respectively.

The Company determines its discount rate assumption for its pension retirement obligations based on indices for AA corporate bonds with an average duration of approximately 20 years for the Japan pension plans and 17 years for the U.S. pension plans, and determination of the U.S. pension plans discount rate utilizes the 85-year extrapolated yield curve. In Japan, participant salary and future salary increases are not factors in determining pension benefit cost or the related pension benefit obligation.

The Company bases its assumption for the long-term rate of return on assets on historical trends (10-year or longer historical rates of return for the Japanese plan assets and 15-year historical rates of return for the U.S. plan assets), expected future market movement, as well as the portfolio mix of securities in the asset portfolio including, but not limited to, style, class and equity and fixed income allocations. In addition, the Company's consulting actuaries evaluate its assumptions for long-term rates of return under Actuarial Standards of Practice (ASOP). Under the ASOP, the actual portfolio type, mix and class is modeled to determine a best estimate of the long-term rate of return. The Company in turn use those results to further validate its own assumptions.
Components of Net Periodic Benefit Cost
Pension and other postretirement benefit expenses are included in acquisition and operating expenses in the consolidated statements of earnings, which includes $25 million, $30 million and $8 million of other components of net periodic pension cost and postretirement costs (other than services costs) for the years ended December 31, 2021, 2020 and 2019, respectively. Total net periodic benefit cost includes the following components:
Pension BenefitsOther
JapanU.S.Postretirement Benefits
(In millions)202120202019202120202019202120202019
Service cost$23 $24 $22 $28 $29 $23 $0 $0 $0 
Interest cost6 5 7 32 34 20 1 1 1 
Expected return on plan assets(8)(7)(6)(41)(35)(29)0 0 0 
Amortization of net actuarial loss2 4 4 30 26 10 3 2 1 
Amortization of prior service cost0 (1)0 0 (2)0 0 0 0 
Net periodic (benefit) cost$23 $25 $27 $49 $52 $24 $4 $3 $2 

Changes in Accumulated Other Comprehensive Income
The following table summarizes the amounts recognized in other comprehensive loss (income) for the years ended December 31:
Pension BenefitsOther
JapanU.S.Postretirement Benefits
(In millions)202120202019202120202019202120202019
Net actuarial loss (gain)$(22)$(14)$1 $(90)$45 $95 $(2)$5 $4 
Amortization of net actuarial loss(2)(4)(4)(30)(26)(10)(3)(2)(1)
Amortization of prior
  service cost 		1 1 0 0 2 0 0 0 0 
     Total$(23)$(17)$(3)$(120)$21 $85 $(5)$3 $3 

No transition obligations arose during 2021.

Benefit Payments
The following table provides expected benefit payments, which reflect expected future service, as appropriate.
Pension BenefitsOther
(In millions)JapanU.S.Postretirement Benefits
2022$17 $32 $5 
202314 32 5 
202416 34 5 
202517 35 4 
202617 37 4 
2027-203188 237 9 

Funding

The Company plans to make contributions of $36 million to the Japanese funded defined benefit plan in 2022. The Company does not plan to make any contributions to the U.S. funded defined benefit plan in 2022. The Company did not make a contribution to the U.S. funded defined benefit plan in 2021. The funding policy for the Company's non-qualified supplemental defined benefit pension plans and other postretirement benefits plan is to contribute the amount of the benefit payments made during the year.
Plan Assets

The investment objective of the Company's Japanese and U.S. funded defined benefit plans is to preserve the purchasing power of the plan's assets and earn a reasonable inflation-adjusted rate of return over the long term. Furthermore, the Company seeks to accomplish these objectives in a manner that allows for the adequate funding of plan benefits and expenses. In order to achieve these objectives, the Company's goal is to maintain a conservative, well-diversified and balanced portfolio of high-quality equity, fixed-income and money market securities. As a part of its strategy, the Company has established strict policies covering quality, type and concentration of investment securities. For the Company's Japanese plan, these policies include limitations on investments in derivatives including futures, options and swaps, and low-liquidity investments such as real estate, venture capital investments, and privately issued securities. For the Company's U.S. plan, these policies prohibit investments in precious metals, limited partnerships, venture capital, and direct investments in real estate. The Company is also prohibited from trading on margin.

The plan fiduciaries for the Company's funded defined benefit plans have developed guidelines for asset allocations reflecting a percentage of total assets by asset class, which are reviewed on an annual basis. Asset allocation targets as of December 31, 2021 were as follows:
Japan PensionU.S. Pension
Domestic equities5 %40 %
International equities21 20 
Fixed income securities66 40 
Other8 0 
     Total100 %100 %

The following table presents the fair value of Aflac Japan's pension plan assets that are measured at fair value on a recurring basis as of December 31. All of these assets are classified as Level 2 in the fair value hierarchy.
(In millions)20212020
Japan pension plan assets:
     Equities:
        Japanese equity securities$21 $20 
        International equity securities86 88 
     Fixed income securities:
        Japanese bonds22 23 
        International bonds252 249 
     Insurance contracts34 36 
        Total$415 $416 
The following table presents the fair value of Aflac U.S.'s pension plan assets that are measured at fair value on a recurring basis as of December 31. All of these assets are classified as Level 1 in the fair value hierarchy.
(In millions)20212020
U.S. pension plan assets:
     Mutual funds:
        Large cap equity funds$297 $234 
        Mid cap equity funds25 24 
        Real estate equity funds0 19 
        International equity funds208 136 
        Fixed income bond funds346 237 
     Aflac Incorporated common stock7 5 
     Cash and cash equivalents2 169 
        Total$885 $824 
The fair values of the Company's pension plan investments categorized as Level 1, consisting of mutual funds and common stock, are based on quoted market prices for identical securities traded in active markets that are readily and regularly available to the Company. The fair values of the Company's pension plan investments classified as Level 2 are based on quoted prices for similar assets in markets that are not active, other inputs that are observable, such as interest rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks, and default rates, or other market-corroborated inputs.

401(k) Plan

The Company sponsors a 401(k) plan in which it matches a portion of U.S. employees' contributions. The plan provides for salary reduction contributions by employees and, in 2021, 2020, and 2019, provided matching contributions by the Company of 100% of each employee's contributions which were not in excess of 4% of the employee's annual cash compensation. The Company also provides a nonelective contribution to the 401(k) plan of 2% of annual cash compensation for employees who opted out of the future benefits of the U.S. defined benefit plan and for new U.S. employees. Effective January 1, 2021, the Company increased this nonelective contribution to 4% of annual compensation.

The 401(k) contributions by the Company, included in acquisition and operating expenses in the consolidated statements of earnings, were $20 million in both 2021 and 2020 and $18 million in 2019. The plan trustee held approximately 2.2 million shares of the Company's common stock for plan participants at December 31, 2021.

Stock Bonus Plan

Aflac U.S. maintains a stock bonus plan for eligible U.S. sales associates. Plan participants receive shares of Aflac Incorporated common stock based on their new annualized premium sales and their first-year persistency of substantially all new insurance policies. The cost of this plan, which was capitalized as deferred policy acquisition costs, amounted to $15 million in 2021 and $24 million in 2020 and $31 million in 2019.

Voluntary Separation Program

In September 2020, the Company announced a voluntary separation program for certain U.S. employees. The program provides eligible employees with a severance package, including twelve months of salary, the employee's targeted bonus payout for 2020 and one year of Consolidated Omnibus Budget Reconciliation Act (COBRA) or retiree medical, if eligible. Employees accepted into this program were notified in October 2020 and most transitions were completed by December 31, 2020, with a small number continuing into the first quarter of 2021. The Company recorded a one-time severance charge of $43 million in the fourth quarter of 2020 related to the program.
v3.22.0.1
COMMITMENTS AND CONTINGENT LIABILITIES
 12 Months Ended
Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]  
COMMITMENTS AND CONTINGENT LIABILITIES COMMITMENTS AND CONTINGENT LIABILITIES
The Company has two outsourcing agreements with a technology and consulting corporation. The first agreement provides mainframe computer operations, distributed mid-range server computer operations, and related support for Aflac Japan. It has a remaining term of three years and an aggregate remaining cost of ¥27.4 billion ($238 million using the December 31, 2021, exchange rate). The second agreement provides application maintenance and development services for Aflac Japan. It has a remaining term of two years and an aggregate remaining cost of ¥2.6 billion ($22 million using the December 31, 2021, exchange rate).

The Company has an outsourcing agreement with a management consulting and technology services company to provide application maintenance and development services for Aflac Japan. The agreement has a remaining term of five years with an aggregate remaining cost of ¥16.0 billion ($140 million using the December 31, 2021, exchange rate).

The Company has two outsourcing agreements with information technology and data services companies to provide application maintenance and development services for Aflac Japan. The first agreement has a remaining term of one year with an aggregate remaining cost of ¥0.6 billion ($5 million using the December 31, 2021, exchange rate). The second agreement has a remaining term of four years with an aggregate remaining cost of ¥10.7 billion ($93 million using the December 31, 2021, exchange rate).
The Company has an enterprise agreement with an information technology and data services company to license software for Aflac Japan. The agreement has a remaining term of two years with an aggregate remaining cost of ¥2.2 billion ($19 million using the December 31, 2021, exchange rate).

The Company is a defendant in various lawsuits considered to be in the normal course of business. Members of the Company's senior legal and financial management teams review litigation on a quarterly and annual basis. The final results of any litigation cannot be predicted with certainty. Although some of this litigation is pending in states where large punitive damages, bearing little relation to the actual damages sustained by plaintiffs, have been awarded in recent years, the Company believes the outcome of pending litigation will not have a material adverse effect on its financial position, results of operations, or cash flows.

See Note 3 of the Notes to the Consolidated Financial Statements for details on certain investment commitments.

Guaranty Fund Assessments

The U.S. insurance industry has a policyholder protection system that is monitored and regulated by state insurance departments. These life and health insurance guaranty associations are state entities (in all 50 states as well as Puerto Rico and the District of Columbia) created to protect policyholders of an insolvent insurance company. All insurance companies (with limited exceptions) licensed to sell life or health insurance in a state must be members of that state’s guaranty association. Under state guaranty association laws, certain insurance companies can be assessed (up to prescribed limits) for certain obligations to the policyholders and claimants of impaired or insolvent insurance companies that write the same line or similar lines of business.

In 2009, the Pennsylvania Insurance Commissioner placed long-term care insurer Penn Treaty Network America Insurance Company and its subsidiary American Network Insurance Company (collectively referred to as Penn Treaty), neither of which is affiliated with Aflac, in rehabilitation and petitioned a state court for approval to liquidate Penn Treaty. A final order of liquidation was granted by a recognized judicial authority on March 1, 2017, and as a result, Penn Treaty is in the process of liquidation. The Company estimated and recognized the impact of its share of guaranty fund assessments resulting from the liquidation using a discounted rate of 4.25%. The Company recognized a discounted liability for the assessments of $62 million (undiscounted $94 million), offset by discounted premium tax credits of $48 million (undiscounted $74 million), for a net $14 million impact to net income in the quarter ended March 31, 2017. The Company paid a majority of these assessments by December 31, 2021. The Company used the cost estimate provided as of the liquidation date by the National Organization of Life and Health Guaranty Associations (NOLHGA) to calculate its estimated assessments and tax credits. Guaranty fund assessments for the years ended December 31, 2021, 2020, and 2019 were immaterial.
v3.22.0.1
SCHEDULE II CONDENSED FINANCIAL INFORMATION OF REGISTRANT
 12 Months Ended
Dec. 31, 2021
Condensed Financial Information Disclosure [Abstract]  
SCHEDULE II CONDENSED FINANCIAL INFORMATION OF REGISTRANT
CONDENSED FINANCIAL INFORMATION OF REGISTRANT

Aflac Incorporated (Parent Only)
Condensed Statements of Earnings
 Years ended December 31,
(In millions)202120202019
Revenues:
   Management and service fees from subsidiaries(1)
$130 $131 $151 
   Net investment income(93)62 77 
   Interest from subsidiaries(1)
2 3 4 
   Net investment gains (losses)206 399 98 
     Total revenues245 595 330 
Operating expenses:
   Interest expense222 221 200 
   Other operating expenses(2)
300 277 221 
     Total operating expenses522 498 421 
   Earnings before income taxes and equity in earnings of
     subsidiaries		(277)97 (91)
Income tax expense (benefit)(144)(15)(22)
   Earnings before equity in earnings of subsidiaries(133)112 (69)
Equity in earnings of subsidiaries(1)
4,458 4,666 3,373 
     Net earnings$4,325 $4,778 $3,304 
(1)Eliminated in consolidation
(2)Includes expense of $48 in 2021 and $15 in 2020 for the early extinguishment of debt
See the accompanying Notes to Condensed Financial Statements.
See the accompanying Report of Independent Registered Public Accounting Firm.
CONDENSED FINANCIAL INFORMATION OF REGISTRANT
Aflac Incorporated (Parent Only)
Condensed Statements of Comprehensive Income (Loss)
  Years ended December 31,
(In millions)202120202019
Net earnings$4,325 $4,778 $3,304 
Other comprehensive income (loss) before income taxes:
Unrealized foreign currency translation gains (losses) during period(889)510 252 
Unrealized gains (losses) on fixed maturity securities during period(960)1,220 5,852 
Unrealized gains (losses) on derivatives during period5 (1)(12)
Pension liability adjustment during period148 (7)(85)
Total other comprehensive income (loss) before income taxes(1,696)1,722 6,007 
Income tax expense (benefit) related to items of other comprehensive
   income (loss)		(155)251 1,543 
Other comprehensive income (loss), net of income taxes(1,541)1,471 4,464 
Total comprehensive income (loss)$2,784 $6,249 $7,768 
See the accompanying Notes to Condensed Financial Statements.
See the accompanying Report of Independent Registered Public Accounting Firm.
CONDENSED FINANCIAL INFORMATION OF REGISTRANT
Aflac Incorporated (Parent Only)
Condensed Balance Sheets
  December 31,
(In millions, except for share and per-share amounts)20212020
Assets:
Investments and cash:
Fixed maturity securities available for sale, at fair value
  (amortized cost $1,608 in 2021 and $1,782 in 2020)
$1,828 $1,876 
Investments in subsidiaries(1)
35,905 36,217 
Other investments1,413 902 
Cash and cash equivalents2,097 2,126 
Total investments and cash41,243 41,121 
Due from subsidiaries(1)
248 253 
Income taxes receivable0 203 
Other assets640 368 
Total assets$42,131 $41,945 
Liabilities and shareholders' equity:
Liabilities:
Employee benefit plans$336 $340 
Notes payable7,579 7,456 
Other liabilities963 590 
Total liabilities8,878 8,386 
Shareholders' equity:
Common stock of $.10 par value. In thousands: authorized 1,900,000
  shares in 2021 and 2020; issued 1,352,739 shares in 2021 and 1,351,018
  shares in 2020
135 135 
Additional paid-in capital2,529 2,410 
Retained earnings41,381 37,984 
Accumulated other comprehensive income (loss):
Unrealized foreign currency translation gains (losses)(2,013)(1,109)
Unrealized gains (losses) on fixed maturity securities9,602 10,361 
Unrealized gains (losses) on derivatives(30)(34)
Pension liability adjustment(166)(284)
Treasury stock, at average cost(18,185)(15,904)
Total shareholders' equity33,253 33,559 
Total liabilities and shareholders' equity$42,131 $41,945 
(1)Eliminated in consolidation
See the accompanying Notes to Condensed Financial Statements.
See the accompanying Report of Independent Registered Public Accounting Firm.
CONDENSED FINANCIAL INFORMATION OF REGISTRANT
Aflac Incorporated (Parent Only)
Condensed Statements of Cash Flows
  Years ended December 31,
(In millions)202120202019
Cash flows from operating activities:
Net earnings$4,325 $4,778 $3,304 
Adjustments to reconcile net earnings to net cash provided from
  operating activities:
              Equity in earnings of subsidiaries(1)
(4,458)(4,666)(3,373)
 Cash dividends received from subsidiaries 2,791 2,060 3,466 
 Other, net408 (331)(203)
Net cash provided (used) by operating activities3,066 1,841 3,194 
Cash flows from investing activities:
Fixed maturity securities sold483 438 340 
Fixed maturity securities purchased(489)(484)(639)
Other investments sold (purchased)(421)(711)(16)
Settlement of derivatives135 4 22 
Additional capitalization of subsidiaries(1)
(161)(291)(214)
Other, net1 2 87 
Net cash provided (used) by investing activities(452)(1,042)(420)
Cash flows from financing activities:
Purchases of treasury stock(2,301)(1,537)(1,627)
Proceeds from borrowings1,153 1,545 347 
Principal payments under debt obligations(700)(350)0 
Dividends paid to shareholders(855)(769)(771)
Treasury stock reissued26 34 49 
Proceeds from exercise of stock options17 12 29 
       Net change in amount due to/from subsidiaries(1)
43 (89)(58)
Other, net(26)(27)(2)
Net cash provided (used) by financing activities(2,643)(1,181)(2,033)
Net change in cash and cash equivalents(29)(382)741 
Cash and cash equivalents, beginning of period2,126 2,508 1,767 
Cash and cash equivalents, end of period$2,097 $2,126 $2,508 
(1)Eliminated in consolidation
See the accompanying Notes to Condensed Financial Statements.
See the accompanying Report of Independent Registered Public Accounting Firm.
(A) Notes Payable
A summary of notes payable as of December 31 follows:
(In millions)20212020
3.625% senior notes paid May 2021
$0 $698 
3.625% senior notes due November 2024
748 747 
3.25% senior notes due March 2025
448 448 
1.125% senior sustainability notes due March 2026
397 0 
2.875% senior notes due October 2026
298 298 
3.60% senior notes due April 2030
991 990 
6.90% senior notes due December 2039
221 221 
6.45% senior notes due August 2040
255 254 
4.00% senior notes due October 2046
394 394 
4.750% senior notes due January 2049
541 541 
Yen-denominated senior notes and subordinated debentures:
.300% senior notes due September 2025 (principal amount ¥12.4 billion)
107 119 
.932% senior notes due January 2027 (principal amount ¥60.0 billion)
520 578 
.500% senior notes due December 2029 (principal amount ¥12.6 billion)
109 121 
.550% senior notes due March 2030 (principal amount ¥13.3 billion)
115 127 
1.159% senior notes due October 2030 (principal amount ¥29.3 billion)
254 282 
.633% senior notes due April 2031 (principal amount ¥30.0 billion)
259 0 
.843% senior notes due December 2031 (principal amount ¥9.3 billion)
81 90 
.750% senior notes due March 2032 (principal amount ¥20.7 billion)
179 198 
.844% senior notes due April 2033 (principal amount ¥12.0 billion)
104 0 
1.488% senior notes due October 2033 (principal amount ¥15.2 billion)
131 146 
.934% senior notes due December 2034 (principal amount ¥9.8 billion)
85 94 
.830% senior notes due March 2035 (principal amount ¥10.6 billion)
91 101 
1.039% senior notes due April 2036 (principal amount ¥10.0 billion)
86 0 
1.750% senior notes due October 2038 (principal amount ¥8.9 billion)
77 85 
1.122% senior notes due December 2039 (principal amount ¥6.3 billion)
54 61 
1.264% senior notes due April 2041 (principal amount ¥10.0 billion)
86 0 
2.108% subordinated debentures due October 2047 (principal amount ¥60.0 billion)
517 575 
1.560% senior notes due April 2051 (principal amount ¥20.0 billion)
172 0 
Yen-denominated loans:
Variable interest rate loan due September 2026 (.41% in 2021 and .43% in 2020,
  principal amount ¥5.0 billion)
43 48 
Variable interest rate loan due September 2029 (.56% in 2021 and .58% in 2020,
  principal amount ¥25.0 billion)
216 240 
Total notes payable$7,579 $7,456 
Amounts in the table above are reported net of debt issuance costs and issuance premiums or discounts, if applicable, that are being amortized over the life of the notes.

In April 2021, the Parent Company issued five series of senior notes totaling ¥82.0 billion through a public debt offering
under its then existing U.S. shelf registration statement. The first series, which totaled ¥30.0 billion, bears interest at a fixed rate of .633% per annum, payable semi-annually, and will mature in April 2031. The second series, which totaled ¥12.0 billion, bears interest at a fixed rate of .844% per annum, payable semi-annually, and will mature in April 2033. The third series, which totaled ¥10.0 billion, bears interest at a fixed rate of 1.039% per annum, payable semi-annually, and will mature in April 2036. The fourth series, which totaled ¥10.0 billion, bears interest at a fixed rate of 1.264% per annum, payable semi-annually, and will mature in April 2041. The fifth series, which totaled ¥20.0 billion, bears interest at a fixed rate of 1.560% per annum, payable semi-annually, and will mature in April 2051. The notes are redeemable at the Parent Company’s option (i) at any time, in whole but not in part, upon the occurrence of certain changes affecting U.S. taxation, as specified in the indenture governing the terms of the issuance or (ii) on or after the date that is six months prior to the stated maturity date of the series, in whole or in part, at a redemption price equal to the aggregate principal amount to be redeemed plus accrued and unpaid interest on the principal amount to be redeemed to, but excluding, the date of redemption.

In May 2021, the Parent Company used a portion of the net proceeds from the April 2021 issuance of its various series of
senior notes to redeem $700 million of the Parent Company's 3.625% senior notes due June 2023.

In March 2021, the Parent Company issued $400 million of senior sustainability notes through a U.S. public debt offering. The notes bear interest at a fixed rate of 1.125% per annum, payable semi-annually, and will mature in March 2026. The Company intends, but is not contractually committed, to allocate an amount at least equivalent to the net proceeds from this issuance exclusively to existing or future investments in, or financing of, assets, businesses or projects that meet the eligibility criteria of the Company's sustainability bond framework described in the offering documentation in connection with such notes. These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 10 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.

The aggregate contractual maturities of notes payable during each of the years after December 31, 2021, are as follows:
(In millions)
2022$0 
20230 
2024750 
2025558 
2026743 
Thereafter5,586 
Total$7,637 

For further information regarding notes payable, see Note 9 of the Notes to the Consolidated Financial Statements.
(B) Derivatives
At December 31, 2021, the Parent Company's outstanding freestanding derivative contracts were swaps, foreign currency forwards and options. The swaps are associated with its notes payable, consisting of cross-currency interest rate swaps, also referred to as foreign currency swaps, associated with the Parent Company's senior notes due in November 2024 and March 2025. The foreign currency forwards and options are designated as derivative hedges of the foreign currency exposure of the Company's net investment in Aflac Japan. The Parent Company does not use derivative financial instruments for trading purposes, nor does it engage in leveraged derivative transactions. For further information regarding these derivatives, see Notes 1, 4 and 9 of the Notes to the Consolidated Financial Statements.
(C) Income Taxes
The Parent Company and its eligible U.S. subsidiaries file a consolidated U.S. federal income tax return. Income tax liabilities or benefits are recorded by each principal subsidiary based upon separate return calculations, and any difference between the consolidated provision and the aggregate amounts recorded by the subsidiaries is reflected in the
Parent Company financial statements. For further information on income taxes, see Note 10 of the Notes to the Consolidated Financial Statements.
(D) Dividend Restrictions

See Note 13 of the Notes to the Consolidated Financial Statements for information regarding dividend restrictions.
(E) Supplemental Disclosures of Cash Flow Information
(In millions)202120202019
Interest paid$213 $209 $189 
Noncash financing activities:
Treasury stock issued for shareholder dividend reinvestment32 29 30 
v3.22.0.1
SCHEDULE III SUPPLEMENTARY INSURANCE INFORMATION
 12 Months Ended
Dec. 31, 2021
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Abstract]  
SCHEDULE III SUPPLEMENTARY INSURANCE INFORMATION SCHEDULE III
SUPPLEMENTARY INSURANCE INFORMATION
Aflac Incorporated and Subsidiaries
Years ended December 31,
(In millions)Deferred Policy
Acquisition
Costs		Future Policy
Benefits & Unpaid
Policy Claims		Unearned
Premiums		Other
Policyholders'
Funds
2021:
Aflac Japan$6,233 $84,079 $2,469 $7,064 
Aflac U.S.3,292 11,798 111 8 
All other0 280 (4)0 
Intercompany eliminations0 (733)0 0 
Total$9,525 $95,424 $2,576 $7,072 
2020:
Aflac Japan$6,991 $91,829 $3,488 $7,811 
Aflac U.S.3,450 11,684 113 13 
All other0 278 (4)0 
Intercompany eliminations0 (821)0 0 
Total$10,441 $102,970 $3,597 $7,824 
Segment amounts may not agree in total to the corresponding consolidated amounts due to rounding.
Years Ended December 31,
(In millions)Net
Earned
Premiums		Net
Investment
Income		Benefits and
Claims, net		Amortization of
Deferred Policy
Acquisition Costs		Other
Operating
Expenses		Premiums
Written
2021:
Aflac Japan$11,853 $3,139 $7,963 $653 $2,555 $11,600 
Aflac U.S.5,614 752 2,447 517 2,048 5,537 
All other180 (73)166 0 435 0 
Total$17,647 $3,818 $10,576 $1,170 $5,038 $17,137 
2020:
Aflac Japan$12,670 $2,856 $8,851 $644 $2,613 $12,312 
Aflac U.S.5,758 702 2,765 570 1,963 5,763 
All other194 80 180 0 402 0 
Total$18,622 $3,638 $11,796 $1,214 $4,978 $18,075 
2019:
Aflac Japan$12,772 $2,753 $8,877 $709 $2,465 $12,367 
Aflac U.S.5,808 720 2,871 573 1,834 5,813 
All other200 105 194 0 339 0 
Total$18,780 $3,578 $11,942 $1,282 $4,638 $18,180 
Segment amounts may not agree in total to the corresponding consolidated amounts due to rounding.
See the accompanying Report of Independent Registered Public Accounting Firm.
v3.22.0.1
SCHEDULE IV REINSURANCE
 12 Months Ended
Dec. 31, 2021
Reinsurance Disclosures [Abstract]  
SCHEDULE IV REINSURANCE
SCHEDULE IV
REINSURANCE
Aflac Incorporated and Subsidiaries
Years Ended December 31,
(In millions)Gross
Amount		Ceded to
Other
Companies		Assumed
from Other
companies		Net
Amount		Percentage
of Amount
Assumed
to Net
2021:
Life insurance in force$134,577 $7,199 $22,568 $149,946 15 %
Premiums:
Health insurance$14,913 $475 $253 $14,691 2 %
Life insurance2,944 29 41 2,956 1 
Total earned premiums$17,857 $504 $294 $17,647 2 %
2020:
Life insurance in force$148,801 $7,016 $20,662 $162,447 13 %
Premiums:
Health insurance$15,682 $526 $213 $15,369 1 %
Life insurance3,273 27 7 3,253 0 
Total earned premiums$18,955 $553 $220 $18,622 1 %
2019:
Life insurance in force$146,585 $6,592 $0 $139,993 0 %
Premiums:
Health insurance$15,657 $527 $205 $15,335 1 %
Life insurance3,465 20 0 3,445 0 
Total earned premiums$19,122 $547 $205 $18,780 1 %
Premiums by type may not agree in total to the corresponding consolidated amounts due to rounding.
See the accompanying Report of Independent Registered Public Accounting Firm.
v3.22.0.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)
 12 Months Ended
Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Description of Business and Basis of Presentation
Description of Business 
Aflac Incorporated (the Parent Company) and its subsidiaries (collectively, the Company) primarily sell supplemental health and life insurance in the United States (U.S.) and Japan. The Company's insurance business is marketed and administered through American Family Life Assurance Company of Columbus (Aflac) in the U.S. and through Aflac Life Insurance Japan Ltd. (ALIJ) in Japan. The Company’s operations consist of two reportable business segments: Aflac U.S., which includes Aflac, and Aflac Japan, which includes ALIJ. American Family Life Assurance Company of New York (Aflac New York) is a wholly owned subsidiary of Aflac. Most of Aflac's policies are individually underwritten and marketed through independent agents.With the exception of dental and vision products administered by Argus Dental & Vision, Inc. (Argus) and certain group life insurance products, Aflac U.S. markets and administers group products through Continental American Insurance Company (CAIC), branded as Aflac Group Insurance. The Company's insurance operations in the U.S. and Japan service the two markets for the Company's insurance business. Aflac Japan's revenues, including net gains and losses on its investment portfolio, accounted for 69% of the Company's total revenues in 2021, compared with 68% in 2020 and 69% in 2019. The percentage of the Company's total assets attributable to Aflac Japan was 82% at December 31, 2021, compared with 83% at December 31, 2020.

In November 2020, the Company, through its insurance subsidiaries Aflac and Aflac New York, acquired Zurich North America’s U.S. Corporate Life and Pensions business (Zurich), which consists of group life, disability and absence management products. Aflac and Aflac New York will reinsure on an indemnity basis Zurich's in-force group life and disability policies. Aflac also acquired assets needed to support the group life and disability business, along with an absence management platform.

In November 2019, the Company acquired Argus Holdings, LLC and its subsidiary Argus Dental & Vision, Inc. (Argus), a benefits management organization and national network dental and vision company, which provides a platform for Aflac Dental and Vision. Argus is an addition to the Aflac U.S. segment.

Basis of Presentation
The Company prepares its financial statements in accordance with U.S. generally accepted accounting principles (U.S. GAAP). These principles are established primarily by the Financial Accounting Standards Board (FASB). In these Notes to the Consolidated Financial Statements, references to U.S. GAAP issued by the FASB are derived from the FASB Accounting Standards CodificationTM (ASC). The preparation of financial statements in conformity with U.S. GAAP requires the Company to make estimates based on currently available information when recording transactions resulting from business operations. The most significant items on the Company's balance sheet that involve a greater degree of accounting estimates and actuarial determinations subject to changes in the future are the valuation of investments and derivatives, deferred policy acquisition costs (DAC), liabilities for future policy benefits and unpaid policy claims, and income taxes. These accounting estimates and actuarial determinations are sensitive to market conditions, investment yields, mortality, morbidity, commission and other acquisition expenses, and terminations by policyholders. As additional information becomes available, or actual amounts are determinable, the recorded estimates are revised and reflected in operating results. Although some variability is inherent in these estimates, the Company believes the amounts provided are reasonable and reflective of the best estimates of management.
The consolidated financial statements include the accounts of the Parent Company, its subsidiaries, and those entities required to be consolidated under applicable accounting standards. All material intercompany accounts and transactions have been eliminated.
Coronavirus Disease 2019 (COVID-19) Coronavirus Disease 2019 (COVID-19): The impact of the COVID-19 global pandemic on the Company continues to evolve. Both Aflac Japan and Aflac U.S. have taken measures to address employee health and safety and increase employees’ ability to develop and maintain more flexible working conditions, with return to office undertaken as warranted by local conditions, and operations have remained stable throughout 2021. The Company continues to monitor its investment portfolios to adjust to market conditions, including the continuing recovery, changes in monetary policy and inflation. Both Aflac Japan and Aflac U.S. have accelerated investments in digital initiatives to improve productivity, efficiency and customer service over the long term. The Company also continues to closely monitor the effects and risks of COVID-19 to assess its impact on economic conditions in Japan and the U.S. and on the Company's business, financial condition, results of operations, liquidity and capital position.
Foreign Currency Translation
Foreign Currency Translation: The functional currency of Aflac Japan is the Japanese yen. The Company translates its yen-denominated financial statement accounts into U.S. dollars as follows. Assets and liabilities are translated at end-of-period exchange rates. Realized gains and losses on security transactions are translated at the exchange rate on the trade date of each transaction. Other revenues, expenses, and cash flows are translated using average exchange rates for the period. The resulting currency translation adjustments are reported in accumulated other comprehensive income. The Company includes in earnings the realized currency exchange gains and losses resulting from foreign currency transactions.

The Parent Company has designated a majority of its yen-denominated liabilities (notes payable and yen-denominated loans) as non-derivative hedges and from time-to-time may designate certain foreign currency forwards and options as derivative hedges of the foreign currency exposure of the Company's net investment in Aflac Japan. Outstanding principal and related accrued interest on these Parent Company liabilities and the fair value of these derivatives are translated into U.S. dollars at end-of-period exchange rates. Currency translation adjustments and changes in the fair value of these derivatives are recorded as unrealized foreign currency translation gains (losses) in other comprehensive income and are included in accumulated other comprehensive income.
Insurance Revenue and Expense Recognition
Insurance Revenue and Expense Recognition: Substantially all of the supplemental health and life insurance policies the Company issues are classified as long-duration contracts. The contract provisions generally cannot be changed or canceled during the contract period; however, the Company may adjust premiums for supplemental health policies issued in the U.S. within prescribed guidelines and with the approval of state insurance regulatory authorities.

Insurance premiums for most of the Company's health and life policies, including cancer, accident, hospital, critical illness, dental, vision, term life, whole life, long-term care and disability, are recognized as earned premiums over the premium-paying periods of the contracts when due from policyholders. When earned premiums are reported, the related amounts of benefits and expenses are charged against such revenues, so that profits are recognized in proportion to earned premiums during the period the policies are expected to remain in force. This association is accomplished by means of annual additions to the liability for future policy benefits and the deferral and subsequent amortization of policy acquisition costs.

Premiums from the Company's products with limited-pay features, including term life, whole life, WAYS, and child endowment, are collected over a significantly shorter period than the period over which benefits are provided. Premiums for these products are recognized as earned premiums over the premium-paying periods of the contracts when due from policyholders. Any gross premium in excess of the net premium is deferred and recorded in earnings, such that profits are recognized in a constant relationship with insurance in force. Benefits are recorded as an expense when they are incurred. A liability for future policy benefits is recorded when premiums are recognized using the net premium method.

At the policyholder's option, customers can also pay discounted advanced premiums for certain of the Company's products. Advanced premiums are deferred and recognized when due from policyholders over the regularly scheduled premium payment period.
The calculation of DAC and the liability for future policy benefits requires the use of estimates based on sound actuarial valuation techniques. For new policy issues, the Company reviews its actuarial assumptions and deferrable acquisition costs each year and revises them when necessary to more closely reflect recent experience and studies of actual acquisition costs. For policies in force, the Company evaluates DAC by major product groupings to determine that they are recoverable from future revenues, and any amounts determined not to be recoverable are charged against net earnings. The Company has not had any material charges to earnings for DAC that was determined not to be recoverable in any of the years presented in this Form 10-K.
Advertising Expense Advertising expense is reported as incurred in insurance expenses in the consolidated statements of earnings.
Cash and Cash Equivalents Cash and Cash Equivalents: Cash and cash equivalents include cash on hand, money market instruments, and other debt instruments with a maturity of 90 days or less when purchased.
Investments
Investments: The Company's debt securities consist of fixed maturity securities, which are classified as either held to maturity or available for sale. Securities classified as held to maturity are securities that the Company has the ability and intent to hold to maturity or redemption and are carried at amortized cost.

All other fixed maturity debt securities are classified as available for sale and are carried at fair value. If the fair value is higher than the amortized cost for debt securities, the excess is an unrealized gain, and if lower than cost, the difference is an unrealized loss. The net unrealized gains and losses on securities available for sale, less related deferred income taxes, are recorded through other comprehensive income and included in accumulated other comprehensive income.

Amortized cost of debt securities is based on the Company's purchase price adjusted for accrual of discount, or amortization of premium, and recognition of impairment charges, if any. The amortized cost of debt securities the Company purchases at a discount or premium will equal the face or par value at maturity or the call date, if applicable. Interest is reported as income when earned and is adjusted for amortization of any premium or discount.

The Company has investments in marketable equity securities which are carried at fair value. Changes in the fair value of equity securities are recorded in earnings as a component of net investment gains and losses.

The Company has investments in variable interest entities (VIEs). Criteria for evaluating VIEs for consolidation focuses on identifying which enterprise has the power to direct the activities of a variable interest entity that most significantly impact the entity's economic performance and (1) the obligation to absorb losses of the entity or (2) the right to receive benefits from the entity. The Company is the primary beneficiary of certain VIEs, and therefore consolidates these entities in its financial statements. While the consolidated VIEs generally operate within a defined set of contractual terms, there are certain powers that are retained by the Company that are considered significant in the conclusion that the Company is the primary beneficiary. These powers vary by structure but generally include the initial selection of the underlying collateral; the ability to obtain the underlying collateral in the event of default; and, the ability to appoint or dismiss key parties in the structure. In particular, the Company's powers surrounding the underlying collateral were considered to be the most significant powers because these most significantly impact the economics of the VIE. The Company has no obligation to provide any continuing financial support to any of the entities in which it is the primary beneficiary. The Company's maximum loss is limited to its original investment. Neither the Company nor any of its creditors have the ability to obtain the underlying collateral, nor does the Company have control over the instruments held in the VIEs, unless there is an event of default. For those entities where the Company is the primary beneficiary, the consolidated entity's assets are segregated on the balance sheet by the caption "consolidated variable interest entities," and consist of fixed maturity securities, equity securities, loan receivables, limited partnerships and derivative instruments.

For the mortgage- and asset-backed securities held in the Company's fixed maturity portfolio, the Company recognizes income using a constant effective yield, which is based on anticipated prepayments and the estimated economic life of the securities. When estimates of prepayments change, the effective yield is recalculated to reflect actual payments to date and anticipated future payments. The net investment in mortgage- and asset-backed securities is adjusted to the amount that would have existed had the new effective yield been applied at the time of acquisition. This adjustment is reflected in net investment income.

The Company uses the specific identification method to determine the gain or loss from securities transactions and report the realized gain or loss in the consolidated statements of earnings as net investment gain or loss. Securities transactions are accounted for based on values as of the trade date of the transaction.

The Company lends fixed maturity and public equity securities to financial institutions in short-term security-lending transactions. These securities continue to be carried as investment assets on the Company's balance sheet during the terms of the loans and are not reported as sales. The Company receives cash or other securities as collateral for such loans. For loans involving unrestricted cash or securities as collateral, the collateral is reported as an asset with a corresponding liability for the return of the collateral. For loans where the Company receives as collateral securities that the Company is not permitted to sell or repledge, the collateral is not reported as an asset.

Commercial mortgage and other loans include transitional real estate loans (TREs), commercial mortgage loans (CMLs) and middle market loans (MMLs). The Company's investments in TREs, CMLs, and MMLs are accounted for as loan receivables and are recorded at amortized cost on the acquisition date. The Company has the intent and ability to hold these loan receivables for the foreseeable future or until they mature and therefore, they are considered held for investment and are carried at amortized cost in the commercial mortgage and other loans line in its consolidated balance sheets. The amortized cost of the loan receivables reflects allowances for expected lifetime losses estimated as of each reporting date.
Other investments include policy loans, limited partnerships, and short-term investments with maturities at the time of purchase of one year or less, but greater than 90 days. Limited partnerships are accounted for using the equity method of accounting. Under the equity method of accounting, the Company reports its proportionate share of the investee's earnings or losses as a component of net investment income in its consolidated statements of earnings. The underlying investments held by the Company’s limited partnerships primarily consist of private equity and real estate. Short-term investments are stated at amortized cost, which approximates fair value.
Credit Losses
Credit Losses: The Company estimates expected lifetime credit losses on financial assets measured at amortized cost including short-term receivables, premiums receivable, held-to-maturity fixed maturity securities, loan receivables, loan commitments and reinsurance recoverables. For available-for-sale fixed maturity securities, the Company evaluates estimated credit losses only when the fair value of the available-for-sale fixed maturity security is below its amortized cost basis. Credit loss changes are recorded as a component of net investment gains and losses for the Company’s held-to-maturity and available-for-sale securities, loan receivables, loan commitments and reinsurance recoverables, whereas credit losses on premium receivables are recorded in net earned premiums in the consolidated statement of earnings. The Company’s off-balance sheet credit exposure is primarily attributable to loan commitments that are not unconditionally cancellable. The Company considers the contractual period of exposure to credit risk, the likelihood that funding will occur, the risk of loss, and the current conditions and expectations of future economic conditions to develop the estimate of expected credit losses. The Company records the estimate of expected credit losses for certain loan commitments within other liabilities in the consolidated balance sheet.

Write-offs and partial write-offs are recorded as a reduction to the amortized cost of the loan or fixed maturity security balance and a corresponding reduction to the credit allowance.

The Company has elected not to measure an allowance on accrued interest income for all asset types, because the uncollectible accrued interest receivable is written off in a timely manner. The Company writes off accrued interest when it is more than ninety days past due by reducing interest income, which is a component of net investment income, in the consolidated statement of earnings.

The Company records due premium receivable net of current expected credit losses in the receivables line item in the consolidated balance sheet, utilizing an aging methodology based on historical loss information, adjusted for current conditions and reasonable and supportable forecasts. Changes in the estimated credit losses related to premium receivable are recorded in net earned premiums in the consolidated statement of earnings.
Prior to January 1, 2020, the Company followed other-than-temporary impairment (OTTI) guidance for its fixed maturity securities to recognize and measure OTTIs for its held-to-maturity and available-for-sale securities. For loans and loan receivables, the amortized cost reflected allowances for expected incurred losses based on past events and current economic conditions as of each reporting date.
Derivatives and Hedging
Derivatives and Hedging: Freestanding derivative instruments are reported in the consolidated balance sheet at fair value and are reported in other assets and other liabilities, with changes in value reported in earnings and/or other comprehensive income. These freestanding derivatives are foreign currency forwards, foreign currency options, foreign currency swaps, interest rate swaps and interest rate swaptions. The Company does not use derivatives for trading purposes, nor does the Company engage in leveraged derivative transactions.

From time to time, the Company purchases certain investments that contain an embedded derivative. The Company assesses whether this embedded derivative is clearly and closely related to the asset that serves as its host contract. If the Company deems that the embedded derivative's terms are not clearly and closely related to the host contract, and a separate instrument with the same terms would qualify as a derivative instrument, the derivative is separated from that contract, held at fair value, and reported with the host instrument in the consolidated balance sheet, with changes in fair value reported in earnings. If the Company has elected the fair value option, the embedded derivative is not bifurcated, and the entire investment is held at fair value with changes in fair value reported in earnings.
See Note 5 for a discussion on how the Company determines the fair value of its derivatives. Accruals on derivatives are typically recorded in other assets or within other liabilities in the consolidated balance sheets.

To qualify for hedge accounting treatment, a derivative must be highly effective in mitigating the designated risk attributable to the hedged item. At the inception of hedging relationships the Company formally documents all relationships between hedging instruments and hedged items, as well as its risk-management objectives and strategies for undertaking the respective hedging relationship, and the methodology that will be used to assess the effectiveness of the hedge relationship at and subsequent to hedge inception. The Company documents the designation of each hedge as
either (i) a hedge of the variability of cash flows to be received or paid related to a recognized asset or liability or the hedge of a forecasted transaction ("cash flow hedge"); (ii) a hedge of the estimated fair value of a recognized asset or liability ("fair value hedge"); or (iii) a hedge of a net investment in a foreign operation ("net investment hedge"). The documentation process includes linking derivatives and non-derivative financial instruments that are designated as hedges to specific assets or groups of assets or liabilities in the statement of financial position or to specific forecasted transactions and defining the effectiveness testing methods to be used. At the hedge inception and on an ongoing quarterly basis, the Company also formally assesses whether the derivatives and non-derivative financial instruments used in hedging activities have been, and are expected to continue to be, highly effective in offsetting their designated risk. Hedge effectiveness is assessed using qualitative and quantitative methods. The assessment of hedge effectiveness determines the accounting treatment of changes in fair value.
For assessing hedge effectiveness, qualitative methods may include the comparison of critical terms of the derivative to the hedged item, and quantitative methods may include regression, dollar offset, or other statistical analysis of changes in fair value or cash flows associated with the hedge relationship.
For derivative instruments that are designated and qualify as cash flow hedges, the effective portion of the gain or loss on the derivative is reported as a component of accumulated other comprehensive income (loss) and reclassified into earnings in the same period or periods during which the hedged transaction affects earnings. In cash flow hedges, all components of each derivative's gain or loss are included in the assessment of hedge effectiveness. The ineffective portion of the change in the fair value of the derivative is recognized in earnings when it occurs.
For derivative instruments that are designated and qualify as fair value hedges, the gain or loss on the hedged item and the portion of the hedging instrument included in the assessment of effectiveness are recorded in the line item of the consolidated statements of earnings in which gain or loss on the hedged item is recorded. When assessing the effectiveness of the Company's fair value hedges, the Company excludes the changes in fair value related to the difference between the spot and the forward rate on its foreign currency forwards, the fair value not resulting from fluctuations in spot currency rates on the final notional exchange on cross currency swaps, and the time value of money of foreign exchange options and interest rate swaptions. For interest rate swaptions and cross-currency interest rate swaps designated under fair value hedges of interest rate risk, the change in the time value of money is recognized in other comprehensive income (loss) and amortized into earnings (net investment income) over its legal term.
As discussed in Note 4, from time to time the Company designates net investment hedges of its net investment in Aflac Japan. The Company makes its net investment hedge designation at the beginning of each quarter. For derivative hedging instruments designated as net investment hedges, Aflac follows the spot-rate method. According to that method, the change in fair value of the hedging instrument due to fluctuations in the spot exchange rate is recorded in the unrealized foreign currency component of other comprehensive income and reclassified to earnings only when the hedged net investment is sold, or when a liquidation of the respective net investment in the foreign entity is substantially completed. If and when a sale or liquidation occurs, the changes in fair value of the derivative deferred in the unrealized foreign currency component of other comprehensive income will be released in the same income statement line item where the gain (loss) on the hedged net investment would be recorded upon sale. All other changes in fair value of the hedging instrument are considered the “excluded component” and are accounted for in net investment gains (losses). Should these designated net investment hedge positions exceed the Company's net investment in Aflac Japan, the foreign exchange effect on the portion that exceeds its investment in Aflac Japan would be recognized in current earnings within net investment gains (losses).
The Company discontinues hedge accounting prospectively when (1) it is determined that the derivative is no longer highly effective in offsetting changes in the estimated cash flows or fair value of a hedged item; (2) the derivative is de-designated as a hedging instrument; or (3) the derivative expires or is sold, terminated or exercised.
When hedge accounting is discontinued on a cash flow hedge or fair value hedge, the derivative is carried in the consolidated balance sheets at its estimated fair value, with changes in estimated fair value recognized in current period earnings. For discontinued cash flow hedges, including those where the derivative is sold, terminated or exercised, amounts previously deferred in other comprehensive income (loss) are reclassified into earnings when earnings are impacted by the cash flow of the hedged item.
If a derivative is not designated as an accounting hedge or its use in managing risk does not qualify for hedge accounting, changes in the estimated fair value of the derivative are generally reported within other gains (losses), which is a component of net investment gains (losses). The fluctuations in estimated fair value of derivatives that have not been designated for hedge accounting can result in volatility in net earnings.
The Company receives and pledges cash or other securities as collateral on open derivative positions. Cash received as collateral is reported as an asset with a corresponding liability for the return of the collateral. Cash pledged as collateral is recorded as a reduction to cash, and a corresponding receivable is recognized for the return of the cash collateral. The Company generally can repledge or resell collateral obtained from counterparties, although the Company does not typically exercise such rights. Securities received as collateral are not recognized unless the Company was to exercise its right to sell that collateral or exercise remedies on that collateral upon a counterparty default. Securities that the Company has pledged as collateral continue to be carried as investment assets on its balance sheet.
Deferred Policy Acquisition Costs
Deferred Policy Acquisition Costs: Certain direct and incremental costs of acquiring insurance contracts are deferred and amortized with interest over the premium payment periods in proportion to the ratio of annual earned premium to total anticipated earned premium. Anticipated earned premium is estimated by using the same mortality, persistency and interest assumptions used in computing liabilities for future policy benefits. In this manner, the related acquisition expenses are matched with revenues. Deferred costs include the excess of current-year commissions over ultimate renewal-year commissions and certain incremental direct policy issue, underwriting and sales expenses. All of these incremental costs are directly related to successful policy acquisition.

For some products, policyholders can elect to modify product benefits, features, rights or coverages by exchanging a contract for a new contract or by amendment, endorsement, or rider to a contract, or by the election of a feature or coverage within a contract. These transactions are known as internal replacements. The Company performs a two-stage analysis of the internal replacements to determine if the modification is substantive to the base policy. The stages of evaluation are as follows: 1) determine if the modification is integrated with the base policy, and 2) if it is integrated, determine if the resulting contract is substantially changed.

For internal replacement transactions where the resulting contract is substantially unchanged, the policy is accounted for as a continuation of the replaced contract. Unamortized deferred acquisition costs from the original policy continue to be amortized over the expected life of the new policy, and the costs of replacing the policy are accounted for as policy maintenance costs and expensed as incurred. Examples include conversions of same age bands, certain family coverage changes, pricing era changes (decrease), ordinary life becomes reduced paid-up and certain reinstatements.

An internal replacement transaction that results in a policy that is substantially changed is accounted for as an extinguishment of the original policy and the issuance of a new policy. Unamortized deferred acquisition costs on the original policy are immediately expensed, and the costs of acquiring the new policy are capitalized and amortized in accordance with the Company's accounting policies for deferred acquisition costs.

Riders can be considered internal replacements that are either integrated or non-integrated resulting in either substantially changed or substantially unchanged treatment. Riders are evaluated based on the specific facts and circumstances of the rider and are considered an expansion of the existing benefits with additional premium required. Non-integrated riders to existing contracts do not change the Company's profit expectations for the related products and are treated as a new policy establishment for incremental coverage.

The Company measures the recoverability of DAC and the adequacy of its policy reserves annually by performing gross premium valuations on its business. (See the following discussion for further information regarding policy reserves.)
Goodwill Goodwill: Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. The amount of goodwill recognized is also impacted by measurement differences resulting from certain assets and liabilities not recorded at fair value (e.g. income taxes, employee benefits). Goodwill is not amortized, but is tested for impairment at a level of a reporting unit at least annually, in the same reporting period each year. Goodwill is included in the line item “Other” assets in the consolidated balance sheets and was $268 million as of December 31, 2021, compared with $269 million at December 31, 2020. A significant majority of the goodwill balance is attributable to the following business combinations within the Aflac U.S. segment, which represents the reporting unit for goodwill impairment testing: (i) CAIC acquisition in 2009, (ii) Empoweredbenefits acquisition in 2015, (iii) Argus acquisition in 2019, and (iv) acquisition of Zurich's business in the fourth quarter of 2020.
Policy Liabilities - Future Policy Benefits Policy Liabilities: Future policy benefits represent insurance claims that are expected to occur in the future and are computed following a net level premium method using estimated future investment yields, persistency and recognized morbidity and mortality tables modified to reflect the Company's experience, including a provision for adverse deviation. These assumptions are generally established and considered locked at policy inception. These assumptions may only be unlocked in certain circumstances based on the results of periodic DAC recoverability and premium deficiency testing.
Policy Liabilities - Unpaid Policy Claims Unpaid policy claims are estimates computed primarily on an undiscounted basis using statistical analyses of historical claims experience adjusted for current trends and changed conditions. The ultimate liability may vary significantly from such estimates. The Company regularly adjusts these estimates as new claims experience emerges and reflects the changes in operating results in the year such adjustments are made.
Unearned Premiums Unearned premiums consist primarily of discounted advance premiums on deposit from policyholders in conjunction with their purchase of certain Aflac Japan limited-pay insurance products. These advanced premiums are deferred upon collection and recognized as earned premiums over the contractual premium payment period.
Other Policy Liabilities Other policyholders’ funds liability consists primarily of the fixed annuity line of business in Aflac Japan which has fixed benefits and premiums.
Internal Replacements of Insurance Contracts For internal replacements that are determined to be substantially changed, policy liabilities related to the original policy that was replaced are immediately released, and policy liabilities are established for the new insurance contract. Further, the policy reserves are evaluated based on the new policy features, and any change (up or down) necessary is recognized at the date of contract change/modification. Examples include conversions to higher age bands, certain family coverage changes, pricing era changes (increase), lapse & re-issue, certain reinstatements and certain other contract conversions. However, for internal replacements that are considered substantially unchanged, no changes to the reserves are recognized.
Reinsurance Reinsurance: The Company enters into reinsurance agreements with other companies in the normal course of business. For each reinsurance agreement, the Company determines if the agreement provides indemnification against loss or liability relating to insurance risk in accordance with applicable accounting standards. Reinsurance premiums and benefits paid or provided are accounted for on bases consistent with those used in accounting for the original policies issued and the terms of the reinsurance contracts. Premiums, benefits and DAC are reported net of insurance ceded.
Income Taxes Income Taxes: Income tax provisions are generally based on pretax earnings reported for financial statement purposes, which differ from those amounts used in preparing the Company's income tax returns. Deferred income taxes are recognized for temporary differences between the financial reporting basis and income tax basis of assets and liabilities, based on enacted tax laws and statutory tax rates applicable to the periods in which the Company expects the temporary differences to reverse. The Company records deferred tax assets for tax positions taken based on its assessment of whether the tax position is more likely than not to be sustained upon examination by taxing authorities. A valuation allowance is established for deferred tax assets when it is more likely than not that an amount will not be realized.
Policyholder Protection Corporation and State Guaranty Association Assessments
Policyholder Protection Corporation and State Guaranty Association Assessments: In Japan, the government has required the insurance industry to contribute to a policyholder protection corporation. The Company recognizes a charge for its estimated share of the industry's obligation once it is determinable. The Company reviews the estimated liability for policyholder protection corporation contributions on an annual basis and reports any adjustments in Aflac Japan's expenses.

In the U.S., each state has a guaranty association that supports insolvent insurers operating in those states. The Company's policy is to accrue assessments when the entity for which the insolvency relates has met its state of domicile's statutory definition of insolvency, the amount of the loss is reasonably estimable and the related premium upon which the assessment is based is written. See Note 15 of the Notes to the Consolidated Financial Statements for further discussion of the guaranty fund assessments charged to the Company.
Treasury Stock Treasury Stock: Treasury stock is reflected as a reduction of shareholders' equity at cost. The Company uses the weighted-average purchase cost to determine the cost of treasury stock that is reissued. The Company includes any gains and losses in additional paid-in capital when treasury stock is reissued.
Share-Based Compensation Share-Based Compensation: The Company measures compensation cost related to its share-based payment transactions at fair value on the grant date, and the Company recognizes those costs in the financial statements over the vesting period during which the employee provides service in exchange for the award. The Company has made an entity-wide accounting policy election to estimate the number of awards that are expected to vest and the corresponding forfeitures.
Earnings Per Share Earnings Per Share: The Company computes basic earnings per share (EPS) by dividing net earnings by the weighted-average number of unrestricted shares outstanding for the period. Diluted EPS is computed by dividing net earnings by the weighted-average number of shares outstanding for the period plus the shares representing the dilutive effect of share-based awards.
Reclassifications Reclassifications: Certain reclassifications have been made to prior-year amounts to conform to current-year reporting classifications. These reclassifications had no impact on net earnings or total shareholders' equity.
Recently Adopted Accounting Pronouncements
New Accounting Pronouncements

Recently Adopted Accounting Pronouncements

ASU 2020-04 Reference Rate Reform: Facilitation of the Effects of Reference Rate Reform on Financial Reporting, as clarified and amended by:
ASU 2021-01 Reference Rate Reform: Relief Extended to Derivatives Impacted by Discounting Transition

In March 2020, the FASB issued amendments that provide optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships, and other transactions affected by the reference rate reform if certain criteria are met. The amendments in this ASU only apply to contracts, hedging relationships, and other transactions that reference the London Interbank Offered Rate (LIBOR) or another reference rate expected to be discontinued because of reference rate reform.

An entity may elect to apply the amendments as of any date from the beginning of an interim period that includes or is subsequent to March 12, 2020, or prospectively from a date within an interim period that includes or is subsequent to March 12, 2020, up to the date that the financial statements are available to be issued.

The amendments generally expire on December 31 2022, i.e., they do not apply to contract modifications made after December 31, 2022, new hedging relationships entered into after December 31, 2022, and hedging relationships evaluated for periods after December 31, 2022.

In January 2021, the FASB issued a standard to permit entities to apply optional expedients in ASC 848 to derivative instruments modified because of discounting transition. Discounting transition refers to the changing of interest rates used for margining, discounting, or contract price alignment of derivative instruments to transition to alternative rates.The amendment is effective immediately.

This standard was adopted on April 1, 2020. The adoption of the new guidance did not have an impact on the Company’s financial statements. The Company will continue to evaluate the impacts of reference rate reform on contract modifications and hedging relationships through December 31, 2022.

ASU 2019-04 Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments

In April 2019, the FASB issued Codification improvements to clarify and correct certain areas of guidance amended as part of ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities; ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments; and ASU 2017-12, Derivative and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities.

The most significant of these improvements to the Company was related to the Codification improvement to ASU 2017-12 and the clarification that a one-time reclassification of assets that are eligible to be hedged under the last-of-layer method (i.e., certain pre-payable securities) from held-to-maturity to available-for-sale is allowed under the new hedge accounting guidance and would not impact the Company’s ability to continue to classify other bonds as held-to-maturity.

The other amendments related to ASU 2017-12 and 2016-01 are either not significant, or were previously implemented as part of the related ASU adoptions.

Applicable amendments related to ASU 2016-13 are discussed within the recent adoption of that update below.

This standard was adopted on January 1, 2020. The adoption of this guidance resulted in a reclassification of $6.9 billion (at amortized cost) of pre-payable fixed-maturity securities from the held-to-maturity to the available-for-sale category. The reclassification resulted in recording in beginning 2020 accumulated other comprehensive income a net unrealized gain of $848 million on an after-tax basis, based on the securities’ fair values on the reclassification date. The reclassification impacted the adoption of ASU 2016-13 (see ASU 2016-13 below for additional details).
ASU 2016-02 Leases, as clarified and amended by:
ASU 2018-01, Leases: Land Easement Practical Expedient for Transition to Topic 842
ASU 2018-10, Codification Improvements to Topic 842, Leases
ASU 2018-11, Leases, Targeted Improvements
ASU 2018-20, Leases: Narrow-Scope Improvements for Lessors

In February 2016, the FASB issued updated guidance for accounting for leases (“Leases Update”). Per the Leases Update, lessees are required to recognize all leases on the balance sheet with the exception of short-term leases. A lease liability will be recorded for the obligation of a lessee to make lease payments arising from a lease. Leases will be classified as finance or operating, with classification affecting the pattern and classification of expense recognition in the income statement. The Leases Update provided a number of optional practical expedients. The Company elected the "package of practical expedients," which permits the Company not to reassess under the new standard its prior conclusions about lease identification, lease classification and initial direct costs. Under the Leases Update, lessor accounting is unchanged.

This standard was adopted on January 1, 2019. The Company has operating and finance leases for office space and equipment. The Company elected the short-term lease exemption for all classes of leases which allows the Company to not recognize right-of-use assets and lease liabilities on the consolidated balance sheet and allows the Company to recognize the lease expense for short-term leases on a straight-line basis over the lease term. The Company elected the practical expedient to not separate lease and non-lease components and applied it to all classes of leases where the non-lease components are not significant. Some of the Company's leases include options to extend or terminate the lease and the lease terms may include such options when it is reasonably certain that the Company will exercise that option. Certain leases also include options to purchase the leased property. The leases within scope of the leases update increased the Company's right-of-use assets and lease liabilities recorded in its beginning 2019 consolidated balance sheet by $134 million.

As of January 1, 2019, the Company did not have land easements, but has elected the practical expedient as a safe harbor.

The Company elected the optional transition method and as a safe harbor, the practical expedient provided to lessors.

The Company has made an accounting policy election to exclude amounts collected from customers for all sales (and other similar) taxes from the transaction price. The adoption of the Leases Update and related amendments did not have a significant impact on the Company's financial position, results of operations, or disclosures.

ASU 2016-13 Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments, as clarified and amended by:
ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815,             Derivatives and Hedging, and Topic 825, Financial Instruments
ASU 2019-05, Financial Instruments - Credit Losses (Topic 326), Targeted Transition Relief
ASU 2019-11, Codification Improvements to Topic 326, Financial Instruments - Credit Losses

In June 2016, the FASB issued amendments that require a financial asset (or a group of financial assets) measured at amortized cost to be presented net of an allowance for credit losses (Credit Losses ASU) in order to reflect the amount expected to be collected on the financial asset(s). The measurement of expected credit losses is amended by replacing the incurred loss impairment methodology with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information. Credit losses on available-for-sale debt securities is measured in a manner similar to prior U.S. GAAP; however, the amendments require that credit losses be presented as an allowance rather than as a write-down. Other amendments include changes to the balance sheet presentation and interest income recognition of purchased financial assets with a more-than-insignificant credit deterioration since origination (PCD financial assets).

This standard was adopted on January 1, 2020. The Company recorded a cumulative effect adjustment with a decrease to beginning 2020 retained earnings of $56 million, net of taxes. See Note 3 of the Notes to the Consolidated Financial Statements for credit loss disclosures. The following line items in the consolidated balance sheets were most significantly impacted by the adoption of the new accounting standard:

•Fixed maturity securities held to maturity, at amortized cost
•Commercial mortgage and other loans
•Reinsurance recoverable, included within Other asset
Description of Accounting Pronouncements Pending Adoption
Accounting Pronouncements Pending Adoption

ASU 2018-12 Financial Services - Insurance: Targeted Improvements to the Accounting for Long-Duration
Contracts, as clarified and amended by:
ASU 2019-09 Financial Services - Insurance: Effective Date
ASU 2020-11 Financial Services - Insurance: Effective Date and Early Application

In August 2018, the FASB issued amendments that will significantly change how insurers account for long-duration contracts. The amendments will change existing recognition, measurement, presentation, and disclosure requirements. Issues addressed in the new guidance include: 1) a requirement to review and, if there is a change, update assumptions for the liability for future policy benefits at least annually, and to update the discount rate assumption quarterly, 2) accounting for market risk benefits at fair value, 3) simplified amortization for deferred acquisition costs, and 4) enhanced financial statement presentation and disclosures.

In November 2019, the FASB issued an amendment extending the effective date for public business entities that meet the definition of an SEC filer, excluding entities eligible to be small reporting companies as defined by the SEC, by one year. In November 2020, the FASB issued an amendment providing an additional year deferral for all insurance entities due to the impact of COVID-19. The amendments are now effective for the Company for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2022. Early application of the amendments is permitted.

The Company continues to evaluate the impact of adoption and expects that the adoption will have a significant impact on the Company’s financial position, results of operations, and disclosures. The Company anticipates that the requirement to update assumptions for liability for future policy benefits (LFPB) will have a significant impact on its results of operations, systems, processes and controls and that the requirement to update discount rates will have a significant impact on its equity.

As part of working toward implementation of the updated standard, the Company has made progress on key accounting policy decisions, including processes to identify insurance policy groupings (cohorts) for LFPB measurement and DAC amortization purposes, applicable discount rates, development of liability cash flow and claim expense assumptions, and DAC amortization methodology.

The Company will not early adopt the updated standard and has selected the modified retrospective transition method. Based upon this transition method, the Company currently estimates that the January 1, 2021 transition date (Transition Date) impact from adoption is likely to result in a decrease in accumulated other comprehensive income (AOCI) in a range between $18 billion and $20 billion. This is due to updating the LFPB discount rate assumptions from the rates locked in for reserves held as of the Transition Date to rates determined by reference to the Transition Date market level yields for upper-medium-grade (low credit risk) fixed income instruments (as of December 31, 2020). The variability around the impact of adoption results from the Company making certain estimates, primarily related to the determination of Transition Date market level yields.

The Company has advanced and continues to refine the design of its discount rate methodology for both the U.S. and Japan insurance business. The methodology incorporates constructing a discount rate curve separately for discounting cash flows used to calculate the U.S. and Japan LFPB, with each curve intended to be reflective of the currency, tenor and characteristics of the insurance liabilities. Discount rates comprising each curve will be determined by reference to upper-medium grade (low credit risk) fixed-income instrument yields that are intended to reflect the duration characteristics of the corresponding insurance liabilities. The Company intends to use for these yields single-A rated fixed income instruments with credit ratings based on international rating standards. Where only local ratings are available, the Company intends to select the fixed-income instruments with local ratings that are equivalent to a single-A rating based on international rating standards. The methodology will be designed to prioritize observable inputs based on market data available in the local debt markets where the respective policies were issued in the currency in which the policies are denominated. For the discount rates applicable to tenors for which the single-A debt market is not liquid or there is little or no observable market data, the Company will use various estimation techniques consistent with the fair value guidance in ASC 820, which include, but are not limited to: (i) for tenors where there is less observable market data and/or the observable market data is available for similar instruments, estimating tenor-specific single-A credit spreads and applying them to risk-free government rates; (ii) for tenors where there is very limited or no observable single-A or similar market data, interpolation and extrapolation techniques. Discount rates will be updated each reporting period.

Long duration insurance contracts issued by the Company will be grouped into annual calendar-year cohorts based on the contract issue date, reportable segment, legal entity and product type. Limited pay contracts will be grouped into separate
cohorts from other traditional products in the same manner and will be further separated based on their premium payment structures. Riders will be combined with base policies with similar insurance coverage types and the same contract issue years.

In addition to the preliminary policy elections related to cohorts and LFPB discount rates directly impacting Transition Date AOCI, the Company has also advanced the following accounting policies relevant to the post-Transition Date accounting:

•Cash flow assumptions underlying insurance liabilities will be evaluated as to whether an update is needed at least annually in the same fiscal quarter each year. To facilitate the review, experience studies will be performed annually in the consistent quarter year-to-year to substantiate assumptions, including mortality, morbidity, and terminations in future periods.
•Locked-in discount rates used for the computation of interest accretion on LFPB for policies issued on or after January 1, 2021 will be determined for each issue-year cohort as a single discount rate, calculated as the weighted-average of monthly upper-medium grade (low-credit risk) fixed-income instrument forward curves over the calendar year, determined using the methodology described above and weighted using issued annualized premiums for each issue month. The single discount rate for each issue-year cohort will remain unchanged after the calendar year of issue. Locked-in discount rates on the policies held at Transition Date reflect the locked-in rates in existence immediately before the Transition Date.
•For DAC amortization, the Company has made a preliminary election to group insurance policies into cohorts that are consistent with the groupings used in estimating the associated LFPB. DAC will be amortized on a constant level basis for the grouped contracts over the expected remaining term of the related contracts. For both life and health products issued by Aflac Japan, the constant-level basis used will be units in force, which is a proxy for face amount and insurance in force, respectively. For life products issued by Aflac U.S., the constant level basis used will be face amount of policies in force; for health products issued by Aflac U.S., the constant level basis used will be the number of policies in force.
•The Company has made a preliminary entity-wide election to use locked-in claim expense assumptions determined for each issue-year cohort as a percentage of incurred claims; these assumptions would remain unchanged over the term of the insurance policy.

The Company has created a governance framework and a plan to support implementation of the updated standard. As part of its implementation plan, the Company has also advanced the modernization of its actuarial technology platform to enhance its modeling, data management, experience study and analytical capabilities, increase the end-to-end automation of key reporting and analytical processes and optimize its control framework. The Company has also put in place internal controls related to the new processes created as part of implementing the updated standard and will continue to refine and maturate these internal controls until the formal implementation in the first quarter of 2023.

The Company has recently begun testing its reporting and disclosure capabilities under the new ASU for post-Transition Date accounting periods.

The Company currently has no products with market risk benefits.
v3.22.0.1
BUSINESS SEGMENT AND FOREIGN INFORMATION (Tables)
 12 Months Ended
Dec. 31, 2021
Segment Reporting [Abstract]  
Reconciliation of Revenue from Segments to Consolidated Information regarding operations by reportable segment and Corporate and other for the years ended December 31 follows:
(In millions)202120202019
Revenues:
Aflac Japan:
   Net earned premiums:
             Cancer$5,829 $6,119 $6,031 
             Medical and other health3,400 3,596 3,582 
             Life insurance2,624 2,955 3,159 
   Adjusted net investment income (1),(2)
3,031 2,659 2,496 
   Other income41 42 45 
               Total adjusted revenue Aflac Japan14,925 15,371 15,313 
Aflac U.S.:
   Net earned premiums:
             Accident/disability2,524 2,614 2,665 
             Cancer1,216 1,275 1,309 
             Other health1,542 1,571 1,548 
             Life insurance332 298 286 
   Adjusted net investment income (3)
754 705 720 
   Other income121 102 22 
           Total adjusted revenue Aflac U.S.6,489 6,565 6,550 
Corporate and other (4), (5)
175 384 393 
           Total adjusted revenues21,589 22,320 22,256 
Net investment gains (losses) (1),(2),(3),(4)
517 (173)51 
           Total revenues$22,106 $22,147 $22,307 
(1) Amortized hedge costs of $76, $206 and $257 in 2021, 2020 and 2019, respectively, related to certain foreign currency exposure management strategies have been reclassified from net investment gains (losses) and reported as a deduction from net investment income when analyzing operations.
(2) Net interest cash flows from derivatives associated with certain investment strategies of $(33), $9, and $(17) in 2021, 2020, and 2019, respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income when analyzing operations.
(3) Net interest cash flows from derivatives associated with certain investment strategies of $2 and $3 in 2021 and 2020, respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income when analyzing operations.
(4) Amortized hedge income of $57, $97 and $89 in 2021, 2020 and 2019, respectively, related to certain foreign currency exposure management strategies has been reclassified from net investment gains (losses) and reported as an increase to net investment income when analyzing operations.
(5) The change in value of federal historic rehabilitation and solar investments in partnerships of $138 in 2021 is included as a reduction to net investment income. Tax credits on these investments of $115 in 2021 has been recorded as an income tax benefit in the consolidated statement of earnings. See Note 3 of the Notes to the Consolidated Financial Statements for additional information on these investments.
Reconciliation of Adjusted Profit (Loss) from Segments to Consolidated
(In millions)202120202019
Pretax earnings:
Aflac Japan (1),(2)
$3,754 $3,263 $3,261 
Aflac U.S. (3)
1,478 1,268 1,272 
Corporate and other (4),(5),(6)
(298)(115)(72)
    Pretax adjusted earnings (7)
4,934 4,416 4,461 
Net investment gains (losses) (1),(2),(3),(4),(5)
462 (229)(15)
Other income (loss) (74)

(28)(1)

    Total earnings before income taxes$5,322 $4,159 $4,445 
Income taxes applicable to pretax adjusted earnings$915 $864 $1,147 
Effect of foreign currency translation on after-tax
  adjusted earnings		(38)31 15 
(1) Amortized hedge costs of $76, $206 and $257 in 2021, 2020 and 2019, respectively, related to certain foreign currency exposure management strategies have been reclassified from net investment gains (losses) and reported as a deduction from net investment income when analyzing operations.
(2) Net interest cash flows from derivatives associated with certain investment strategies of $(33), $9, and $(17) in 2021, 2020, and 2019, respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income when analyzing operations.
(3) Net interest cash flows from derivatives associated with certain investment strategies of $2 and $3 in 2021 and 2020, respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income when analyzing operations.
(4) Amortized hedge income of $57, $97 and $89 in 2021, 2020 and 2019, respectively, related to certain foreign currency exposure management strategies has been reclassified from net investment gains (losses) and reported as an increase to net investment income when analyzing operations.
(5) A gain of $55, $56 and $66 in 2021, 2020 and 2019, respectively, related to the interest rate component of the change in fair value of foreign currency swaps on notes payable has been reclassified from net investment gains (losses) and included in adjusted earnings when analyzing operations.
(6) The change in value of federal historic rehabilitation and solar investments in partnerships of $138 in 2021 is included as a reduction to net investment income. Tax credits on these investments of $115 in 2021 has been recorded as an income tax benefit in the consolidated statement of earnings. See Note 3 of the Notes to the Consolidated Financial Statements for additional information on these investments.
(7) Includes $170, $167 and $135 of interest expense on debt in 2021, 2020 and 2019, respectively.
Reconciliation of Assets from Segment to Consolidated
Assets as of December 31 were as follows:
(In millions)20212020
Assets:
Aflac Japan$128,536 $137,271 
Aflac U.S.23,106 22,864 
Corporate and other5,900 4,951 
    Total assets$157,542 $165,086 
Foreign Currency Disclosure
Yen-Translation Effects: The following table shows the yen/dollar exchange rates used for or during the periods ended December 31. Exchange effects were calculated using the same yen/dollar exchange rate for the current year as for each respective prior year.
202120202019
Statements of Earnings:
Weighted-average yen/dollar exchange rate (1)
109.79 106.86 109.07 
Yen percent strengthening (weakening)(2.7)%2.1 %1.2 %
Exchange effect on pretax adjusted earnings (in millions)$(47)$38 $20 
20212020
Balance Sheets:
Yen/dollar exchange rate at December 31(1)
115.02 103.50 
Yen percent strengthening (weakening)(10.0)%5.9 %
Exchange effect on total assets (in millions)$(9,635)$7,970 
Exchange effect on total liabilities (in millions)(7,566)7,870 
(1) Rates are based on the published MUFG Bank, Ltd. telegraphic transfer middle rate (TTM)
Schedule of Intercompany Transfers of Funds Information on transfers for each of the years ended December 31 is shown below. See Note 13 for information concerning restrictions on transfers from Aflac Japan.
(In millions)202120202019
Management fees$59 $71 $75 
Allocated expenses0 0 4 
Profit remittances2,138 1,215 2,070 
Total transfers from Aflac Japan$2,197 $1,286 $2,149 
Property, Plant and Equipment Classes of property and equipment as of December 31 were as follows:
(In millions)20212020
Property and equipment:
Land$168 $168 
Buildings491 523 
Equipment and furniture542 566 
Total property and equipment1,201 1,257 
Less accumulated depreciation663 656 
Net property and equipment$538 $601 
v3.22.0.1
INVESTMENTS (Tables)
 12 Months Ended
Dec. 31, 2021
Schedule Of Net Investment Income
The components of net investment income for the years ended December 31 were as follows:
(In millions)202120202019
Fixed maturity securities$3,068 $3,113 $3,141 
Equity securities35 29 37 
Commercial mortgage and other loans570 545 468 
Other investments (1)
356 145 53 
Short-term investments and cash equivalents7 18 56 
Gross investment income4,036 3,850 3,755 
Less investment expenses218 212 177 
Net investment income$3,818 $3,638 $3,578 
(1) The change in value of federal historic rehabilitation and solar investments in partnerships of $138 in 2021 is included as a reduction to net investment income. Tax credits on these investments of $115 in 2021 have been recorded as an income tax benefit in the consolidated statement of earnings.
Available-for-Sale Debt Securities
The amortized cost for the Company's investments in fixed maturity securities, the cost for equity securities and the fair values of these investments at December 31 are shown in the following tables.
  2021
(In millions)
Amortized
Cost		Allowance for Credit LossesGross
Unrealized
Gains		Gross
Unrealized
Losses		  Fair
  Value
Securities available for sale, carried at fair
  value through other comprehensive income:
Fixed maturity securities:
  Yen-denominated:
Japan government and agencies$30,335 $0 $3,343 $61 $33,617 
Municipalities1,192 0 322 5 1,509 
Mortgage- and asset-backed securities300 0 19 1 318 
Public utilities4,462 0 906 2 5,366 
Sovereign and supranational760 0 82 0 842 
Banks/financial institutions6,963 0 787 72 7,678 
Other corporate7,148 0 1,535 26 8,657 
Total yen-denominated51,160 0 6,994 167 57,987 
  U.S. dollar-denominated:
U.S. government and agencies196 0 8 1 203 
Municipalities1,340 0 189 2 1,527 
Mortgage- and asset-backed securities897 0 33 2 928 
Public utilities3,781 0 909 5 4,685 
Sovereign and supranational222 0 57 6 273 
Banks/financial institutions3,169 0 747 3 3,913 
Other corporate24,604 0 4,629 53 29,180 
Total U.S. dollar-denominated34,209 0 6,572 72 40,709 
Total securities available for sale$85,369 $0 $13,566 $239 $98,696 
 
2020
(In millions)Amortized
Cost		Allowance for Credit LossesGross
Unrealized
Gains		Gross
Unrealized
Losses		Fair
  Value
Securities available for sale, carried at fair value
  through other comprehensive income:
Fixed maturity securities:
  Yen-denominated:
Japan government and agencies$32,959 $0 $4,182 $52 $37,089 
Municipalities1,324 0 374 5 1,693 
Mortgage- and asset-backed securities342 0 27 1 368 
Public utilities4,777 0 1,096 1 5,872 
Sovereign and supranational981 0 108 0 1,089 
Banks/financial institutions7,552 0 886 102 8,336 
Other corporate8,114 0 1,747 37 9,824 
Total yen-denominated56,049 0 8,420 198 64,271 
  U.S. dollar-denominated:
U.S. government and agencies245 0 16 0 261 
Municipalities1,154 0 173 2 1,325 
Mortgage- and asset-backed securities667 0 8 5 670 
Public utilities4,013 0 947 15 4,945 
Sovereign and supranational232 0 64 3 293 
Banks/financial institutions2,973 0 758 7 3,724 
Other corporate26,297 38 4,385 251 30,393 
Total U.S. dollar-denominated35,581 38 6,351 283 41,611 
Total securities available for sale$91,630 $38 $14,771 $481 $105,882 
Held-to-Maturity Securities
  2021
(In millions)
Amortized
Cost		Allowance for Credit LossesNet Carrying AmountGross
Unrealized
Gains		Gross
Unrealized
Losses		Fair  
Value  
Securities held to maturity, carried at
  amortized cost:
Fixed maturity securities:
  Yen-denominated:
Japan government and agencies$21,089 $3 $21,086 $4,613 $0 $25,699 
Municipalities335 0 335 101 0 436 
Public utilities44 1 43 12 0 55 
Sovereign and supranational518 4 514 136 0 650 
Other corporate22 0 22 7 0 29 
Total yen-denominated22,008 8 22,000 4,869 0 26,869 
Total securities held to maturity$22,008 $8 22,000 $4,869 $0 $26,869 
  2020
(In millions)Amortized
Cost		Allowance for Credit LossesNet Carrying AmountGross
Unrealized
Gains		Gross
Unrealized
Losses		Fair  
Value
Securities held to maturity, carried at
  amortized cost:
Fixed maturity securities:
  Yen-denominated:
Japan government and agencies$23,448 $3 $23,445 $5,625 $0 $29,070 
Municipalities377 0 377 122 0 499 
Public utilities48 1 47 14 0 61 
Sovereign and supranational577 6 571 165 0 736 
Other corporate24 0 24 9 0 33 
Total yen-denominated24,474 10 24,464 5,935 0 30,399 
Total securities held to maturity$24,474 $10 $24,464 $5,935 $0 $30,399 
Equity Securities, FV-NI
  
20212020
(In millions)Fair ValueFair Value
Equity securities, carried at fair value through net earnings:
Equity securities:
      Yen-denominated$744 $680 
      U.S. dollar-denominated817 603 
      Other currencies42 0 
Total equity securities$1,603 $1,283 
Investments Classified by Contractual Maturity Date
The contractual and economic maturities of the Company's investments in fixed maturity securities at December 31, 2021, were as follows:
(In millions)
Amortized
Cost (1)
Fair
Value
Available for sale:
Due in one year or less$984 $1,015 
Due after one year through five years8,145 8,782 
Due after five years through 10 years13,288 15,491 
Due after 10 years61,755 72,163 
Mortgage- and asset-backed securities1,197 1,245 
Total fixed maturity securities available for sale$85,369 $98,696 
Held to maturity:
Due in one year or less$0 $0 
Due after one year through five years44 48 
Due after five years through 10 years10,121 11,772 
Due after 10 years11,835 15,049 
Mortgage- and asset-backed securities0 0 
Total fixed maturity securities held to maturity$22,000 $26,869 
(1) Net of allowance for credit losses
Investment Exposures Exceeding 10 Percent Shareholders Equity
Investment exposures that individually exceeded 10% of shareholders' equity as of December 31 were as follows:
20212020
(In millions)Credit
Rating		Amortized
Cost		Fair
Value		Credit
Rating		Amortized
Cost		Fair
Value
Japan National Government(1)
A+$50,186$57,862A+$55,153$64,657
(1)Japan Government Bonds (JGBs) or JGB-backed securities
Gain (Loss) on Investments Information regarding pretax net gains and losses from investments for the years ended December 31 follows:
(In millions)202120202019
Net investment gains (losses):
Sales and redemptions:
Fixed maturity securities available for sale:
Gross gains from sales$64 $31 $115 
Gross losses from sales(52)(47)(68)
Foreign currency gains (losses) on sales and redemptions1 (69)(16)
Total sales and redemptions13 (85)31 
Equity securities164 184 

101 
Loan loss reserves (1)
0 0 (18)
Credit losses:
Fixed maturity securities available for sale 38 (38)0 
Fixed maturity securities held to maturity1 1 0 
Commercial mortgage and other loans6 (93)0 
Impairment losses (2)
(20)(49)(13)
Loan commitments4 (21)0 
Reinsurance recoverables and other(2)0 0 
Total credit losses27 (200)(13)
Derivatives and other:
Derivative gains (losses)(805)399 (174)
Foreign currency gains (losses)1,069 (568)(62)
Total derivatives and other264 (169)(236)
Total net investment gains (losses)$468 $(270)$(135)
(1) U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only
(2) Includes OTTI losses in 2019
Unrealized Gain (Loss) on Investments
Information regarding changes in unrealized gains and losses from investments recorded in AOCI for the years ended December 31 follows:
(In millions)202120202019
Changes in unrealized gains (losses):
Fixed maturity securities, available for sale$(960)$2,399 $5,852 
Total change in unrealized gains (losses)$(960)$2,399 $5,852 
Net Effect on Shareholders' Equity of Unrealized Gains and Losses from Investment Securities
The net effect on shareholders' equity of unrealized gains and losses from fixed maturity securities at December 31 was as follows:
(In millions)20212020
Unrealized gains (losses) on securities available for sale$13,330 $14,290 
Deferred income taxes(3,728)(3,929)
Shareholders’ equity, unrealized gains (losses) on fixed maturity securities$9,602 $10,361 
Investments Gross Unrealized Loss Aging
The following tables show the fair values and gross unrealized losses of the Company's available-for-sale investments, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at December 31.
 
  2021
  TotalLess than 12 months12 months or longer
(In millions)Fair
Value		Unrealized
Losses		Fair
Value		Unrealized
Losses		Fair
Value		Unrealized
Losses
Fixed maturity securities available
   for sale:
  U.S. government and
      agencies:
  U.S. dollar-denominated$1 $1 $0 $1 $1 $0 
  Japan government and
      agencies:
  Yen-denominated2,868 61 445 3 2,423 58 
  Municipalities:
  U.S. dollar-denominated82 2 79 2 3 0 
  Yen-denominated187 5 53 0 134 5 
Mortgage- and asset-
    backed securities:
  U.S. dollar-denominated278 2 278 2 0 0 
  Yen-denominated33 1 0 0 33 1 
  Public utilities:
  U.S. dollar-denominated130 5 70 2 60 3 
  Yen-denominated26 2 0 0 26 2 
  Sovereign and supranational:
  U.S. dollar-denominated37 6 6 1 31 5 
  Banks/financial institutions:
  U.S. dollar-denominated292 3 274 3 18 0 
  Yen-denominated2,074 72 1,011 16 1,063 56 
  Other corporate:
  U.S. dollar-denominated1,365 53 458 8 907 45 
  Yen-denominated 541 26 274 4 267 22 
  Total$7,914 $239 $2,948 $42 $4,966 $197 
  2020
  TotalLess than 12 months12 months or longer
(In millions)Fair
Value		Unrealized
Losses		Fair
Value		Unrealized
Losses		Fair
Value		Unrealized
Losses
Fixed maturity securities available
   for sale:
  Japan government and
      agencies:
  Yen-denominated$2,604 $52 $2,604 $52 $0 $0 
  Municipalities:
  U.S. dollar-denominated94 2 94 2 0 0 
  Yen-denominated183 5 169 4 14 1 
Mortgage- and asset-
    backed securities:
  U.S. dollar-denominated360 5 360 5 0 0 
  Yen-denominated37 1 37 1 0 0 
  Public utilities:
  U.S. dollar-denominated326 15 208 7 118 8 
  Yen-denominated135 1 135 1 0 0 
  Sovereign and supranational:
U.S. dollar-denominated39 3 39 3 0 0 
  Banks/financial institutions:
  U.S. dollar-denominated82 7 44 1 38 6 
  Yen-denominated1,809 102 765 36 1,044 66 
  Other corporate:
  U.S. dollar-denominated4,499 251 2,157 59 2,342 192 
  Yen-denominated613 37 290 13 323 24 
  Total $10,781 $481 $6,902 $184 $3,879 $297 
Commercial Mortgage and Other Loans by Property Type
The table below reflects the composition of the carrying value for commercial mortgage and other loans by property type as of December 31.
(In millions)20212020
Amortized Cost% of TotalAmortized Cost% of Total
Commercial Mortgage and other loans
  Transitional real estate loans:
    Office$2,001 16.7 $2,115 19.7 
    Retail267 2.2 125 1.2 
    Apartments/Multi-Family1,893 15.8 1,782 16.6 
    Industrial94 .8 85 .8 
    Hospitality876 7.3 1,106 10.3 
    Other228 1.9 81 .7 
        Total transitional real estate loans5,359 44.7 5,294 49.3 
Commercial mortgage loans:
     Office398 3.3 401 3.7 
     Retail332 2.8 340 3.2 
     Apartments/Multi-Family649 5.4 588 5.5 
     Industrial525 4.4 391 3.6 
        Total commercial mortgage loans1,904 15.9 1,720 16.0 
Middle market loans4,697 39.4 3,720 34.7 
        Total commercial mortgage and other loans$11,960 100.0 $10,734 100.0 
Allowance for credit losses(174)(180)
              Total net commercial mortgage and other loans$11,786 $10,554 
Financing Receivable, Allowance for Credit Loss The following table presents the roll forward of the allowance for credit losses by portfolio segment for the years ended December 31.
(In millions)Transitional Real Estate LoansCommercial Mortgage LoansMiddle Market LoansHeld to Maturity SecuritiesAvailable for Sale SecuritiesReinsurance Recoverables
Balance at December 31, 2019 (1)
$(22)$(3)$(20)$0 $0 $0 
Transition impact to retained earnings(2)(8)(33)(10)0 (11)
(Addition to) release of allowance for credit
  losses		(39)(21)(41)0 (75)(1)
Write-offs, net of recoveries0 0 9 0 37 0 
Balance at December 31, 2020(63)(32)(85)(10)(38)(12)
(Addition to) release of allowance for credit
  losses		(5)22 (11)1 26 (2)
Write-offs, net of recoveries0 0 0 0 12 0 
Change in foreign exchange0 0 0 1 0 1 
Balance at December 31, 2021$(68)$(10)$(96)$(8)$0 $(13)
(1) U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only.
Other Investments
The table below reflects the composition of the carrying value for other investments as of December 31.
(In millions)20212020
Other investments:
Policy loans$236 $260 
Short-term investments (1)
1,726 1,139 
Limited partnerships1,858 1,004 
Other22 26 
Total other investments$3,842 $2,429 
(1) Includes securities lending collateral
Securities Lending Transactions Accounted for as Secured Borrowings
Details of collateral by loaned security type and remaining maturity of the agreements as of December 31 were as follows:
Securities Lending Transactions Accounted for as Secured Borrowings
Remaining Contractual Maturity of the Agreements
20212020
(In millions)
Overnight
and
Continuous(1)
Up to 30
days		Total
Overnight
and
Continuous(1)
Up to 30
days		Total
Securities lending transactions:
Fixed maturity securities:
Japan government and
  agencies		$0 $920 $920 $0 $0 $0 
Public utilities40 0 40 57 0 57 
Sovereign and supranational2 0 2 3 0 3 
Banks/financial institutions88 0 88 63 0 63 
Other corporate1,112 0 1,112 841 0 841 
          Total borrowings$1,242 $920 $2,162 $964 $0 $964 
Gross amount of recognized liabilities for securities
   lending transactions		$2,162 $964 
(1) The related loaned security, under the Company's U.S. securities lending program, can be returned to the Company at the transferee's discretion; therefore, they are classified as Overnight and Continuous.
Variable Interest Entity, Consolidated  
Investments in Variable Interest Entities
The following table presents the cost or amortized cost, fair value and balance sheet caption in which the assets and liabilities of consolidated VIEs are reported as of December 31.
Investments in Consolidated Variable Interest Entities
  20212020
(In millions)
Amortized
Cost (1)
Fair
Value
Amortized
Cost (1)
Fair
Value
Assets:
Fixed maturity securities, available for sale$3,264 $4,490 $3,487 $4,596 
Commercial mortgage and other loans9,740 9,910 8,964 9,040 
Other investments (2)
1,535 1,535 826 826 
Other assets (3)
78 78 133 133 
Total assets of consolidated VIEs$14,617 $16,013 $13,410 $14,595 
Liabilities:
Other liabilities (3)
$414 $414 $231 $231 
Total liabilities of consolidated VIEs$414 $414 $231 $231 
(1) Net of allowance for credit losses
(2) Consists entirely of alternative investments in limited partnerships
(3) Consists entirely of derivatives
Variable Interest Entity, Not Consolidated  
Investments in Variable Interest Entities The table below reflects the amortized cost, fair value and balance sheet caption in which the Company's investment in VIEs not consolidated are reported as of December 31.
Investments in Variable Interest Entities Not Consolidated
20212020
(In millions)Amortized
Cost		Fair
Value		Amortized
Cost		Fair
Value
Assets:
Fixed maturity securities, available for sale$4,779 $5,864 $5,477 $6,767 
Other investments (1)
323 323 178 178 
Total investments in VIEs not consolidated$5,102 $6,187 $5,655 $6,945 
(1) Consists entirely of alternative investments in limited partnerships
Transitional real estate loans  
Financing Receivable Credit Quality Indicators
The following tables present as of December 31, 2021 the amortized cost basis of TREs, CMLs and MMLs by year of origination and credit quality indicator.
Transitional Real Estate Loans
(In millions)20212020201920182017PriorTotal
Loan-to-Value Ratio:
0%-59.99%$866 $36 $502 $85 $0 $0 $1,489 
60%-69.99%620 136 840 465 50 0 2,111 
70%-79.99%846 153 312 279 73 0 1,663 
80% or greater68 28 0 0 0 0 96 
Total$2,400 $353 $1,654 $829 $123 $0 $5,359 
Commercial mortgage loans  
Financing Receivable Credit Quality Indicators
Commercial Mortgage Loans
(In millions)20212020201920182017PriorTotalWeighted-Average DSCR
Loan-to-Value Ratio:
0%-59.99%$306 $47 $522 $167 $68 $535 $1,645 2.53
60%-69.99%34 0 86 0 0 114 234 1.92
70%-79.99%0 0 0 0 0 25 25 1.65
80% or greater0 0 0 0 0 0 0 0.00
Total$340 $47 $608 $167 $68 $674 $1,904 2.45
Weighted Average DSCR2.831.932.462.292.752.30
Middle market loans  
Financing Receivable Credit Quality Indicators
Middle Market Loans
(In millions)20212020201920182017PriorRevolving LoansTotal
Credit Ratings:
BBB$136 $67 $43 $24 $0 $0 $72 $342 
BB353 332 234 134 42 24 275 1,394 
B721 482 568 267 179 111 246 2,574 
CCC0 22 64 60 79 47 74 346 
CC0 0 0 14 26 0 1 41 
C and lower0 0 0 0 0 0 0 0 
Total$1,210 $903 $909 $499 $326 $182 $668 $4,697 
v3.22.0.1
DERIVATIVE INSTRUMENTS (Tables)
 12 Months Ended
Dec. 31, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value
20212020
(In millions)Asset
Derivatives		Liability
Derivatives		Asset
Derivatives		Liability
Derivatives
Hedge Designation/ Derivative
  Type		Notional
Amount		Fair ValueFair ValueNotional
Amount		Fair ValueFair Value
Cash flow hedges:
Foreign currency swaps - VIE$18 $0 $2 $18 $0 $1 
Total cash flow hedges18 0 2 18 0 1 
Fair value hedges:
Foreign currency forwards62 0 5 64 2 0 
Foreign currency options8,829 5 0 8,865 0 0 
Total fair value hedges8,891 5 5 8,929 2 0 
Net investment hedge:
Foreign currency forwards4,996 341 0 5,010 14 84 
Foreign currency options1,949 0 0 2,027 1 0 
Total net investment hedge6,945 341 0 7,037 15 84 
Non-qualifying strategies:
Foreign currency swaps2,250 59 13 2,250 47 81 
Foreign currency swaps - VIE3,151 78 412 2,857 133 230 
Foreign currency forwards15,953 450 1,133 26,528 386 301 
Foreign currency options2,746 3 0 11,037 0 0 
Interest rate swaps3,500 0 54 0 0 0 
Total non-qualifying strategies27,600 590 1,612 42,672 566 612 
Total derivatives$43,454 $936 $1,619 $58,656 $583 $697 
Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location
The following table presents the gains and losses on derivatives and the related hedged items in fair value hedges for the years ended December 31.
Fair Value Hedging Relationships
(In millions)Hedging DerivativesHedged Items
Hedging DerivativesHedged Items Total
Gains
(Losses)
Gains (Losses)
Excluded from Effectiveness Testing(1)
Gains (Losses)
Included in Effectiveness Testing(2)
 Gains (Losses)(2)
Net Investment Gains (Losses) Recognized for Fair Value Hedge
2021:
Foreign currency forwardsFixed maturity securities$(7)$0 $(7)$6 $(1)
Foreign currency optionsFixed maturity securities(26)(25)(1)4 3 
Total gains (losses)$(33)$(25)$(8)$10 $2 
2020:
Foreign currency forwardsFixed maturity securities$(14)$(8)$(6)$7 $1 
Foreign currency optionsFixed maturity securities(9)(8)(1)1 0 
Total gains (losses)$(23)$(16)$(7)$8 $1 
2019:
Foreign currency forwardsFixed maturity securities$(50)$(64)$14 $(12)$2 
Foreign currency optionsFixed maturity securities(7)(7)0 0 0 
Interest rate
swaptions		Fixed maturity securities(9)(9)0 0 0 
    Total gains (losses)$(66)$(80)$14 $(12)$2 
(1) Gains (losses) excluded from effectiveness testing includes the forward point on foreign currency forwards and time value change on foreign currency options which are reported in the consolidated statement of earnings as net investment gains (losses). It also includes the change in the fair value of the interest rate swaptions related to the time value of the swaptions which is recognized as a component of other comprehensive income (loss).
(2) Gains and losses on foreign currency forwards and options and related hedged items are reported in the consolidated statement of earnings as net investment gains (losses). For interest rate swaptions and related hedged items, gains and losses included in the hedge assessment, premium amortization and time value amortization while the hedge items are still outstanding are reported within net investment income. The time value gains and losses for interest rate swaptions when the related hedged items are redeemed are reported in net investment gains and losses consistent with the impact of the hedged item. For the years ended December 31, 2021 and 2020, gains and losses included in the hedge assessment on interest rate swaptions and related hedged items were immaterial.
Schedule of Interest Rate Fair Value Hedges Hedged Items
The following table shows the carrying amounts of assets designated and qualifying as hedged items in fair value hedges of interest rate risk and the related cumulative hedge adjustment included in the carrying amount as of December 31.
(In millions)
Carrying Amount of the Hedged Assets/(Liabilities)(1)
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Assets/(Liabilities)
2021202020212020
Fixed maturity securities$3,038 $4,331 $205 $237 
(1) The balance includes hedging adjustment on discontinued hedging relationships of $205 in 2021 and $237 in 2020.
Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance
The following table summarizes the impact to earnings and other comprehensive income (loss) from all derivatives and hedging instruments for the years ended December 31.
202120202019
(In millions)
Net Investment Income (1)
Net Investment
Gains (Losses)
Other
Comprehensive
Income (Loss)(2)
Net Investment Income (1)
Net Investment
Gains (Losses)
Other
Comprehensive
Income (Loss)(2)
Net Investment Income (1)
Net Investment
Gains (Losses)
Other
Comprehensive
Income (Loss)(2)
Qualifying hedges:
  Cash flow hedges:
       Foreign currency swaps - VIE$(1)$(4)$3 $(1)$0 $(2)$(2)$(1)$(4)
  Total cash flow hedges(1)(4)
(3)
3 (1)0 
(3)
(2)(2)(1)
(3)
(4)
  Fair value hedges:
       Foreign currency forwards (3)
(1)(7)(62)
       Foreign currency options (3)
(22)(8)(7)
       Interest rate swaptions (3)
(1)(1)2 (1)0 1 (1)0 (8)
  Total fair value hedges(1)(24)2 (1)(15)1 (1)(69)(8)
  Net investment hedge:
       Non-derivative hedging
          instruments		0 328 0 (135)0 (24)
       Foreign currency forwards29 525 149 (282)10 83 
       Foreign currency options (4)0 (5)0 (4)0 
   Total net investment hedge25 853 144 (417)6 59 
  Non-qualifying strategies:
       Foreign currency swaps135 29 90 
       Foreign currency swaps - VIE(188)(122)(68)
       Foreign currency forwards(707)311 (148)
       Foreign currency options (3)(3)0 
       Interest rate swaps(38)49 17 
Forward bond purchase
  commitment - VIE		(1)6 0 
  Total non-qualifying strategies(802)270 (110)
          Total$(2)$(805)$858 $(2)$399 $(418)$(3)$(174)$47 
(1) Interest expense/income on cash flow hedges are recorded in net investment income. For interest rate swaptions classified as fair value hedges, the change in the time value of the swaptions is recognized in other comprehensive income (loss) and amortized into net investment income over its legal term. If the swaption is early terminated but the hedge item is still outstanding, the amortization of disposal amount of the swaptions is recorded in net investment income over the remaining life of the hedged items.
(2) Gains and losses on cash flow hedges and the change in the fair value of interest rate swaptions related to the time value of the swaptions in fair value hedges are recorded as unrealized gains (losses). Gains and losses on net investment hedges related to changes in foreign currency spot rates are recorded in the unrealized foreign currency translation gains (losses) line in the consolidated statement of comprehensive income (loss).
(3) Impact of cash flow hedges reported as net investment gains (losses) includes $4 of losses reclassified from accumulated other comprehensive income (loss) into earnings during the year ended December 31, 2021, and an immaterial amount during the years ended December 31, 2020 and 2019, respectively. In addition, $2 of losses were reclassified from accumulated other comprehensive income (loss) into earnings during the year ended December 31, 2021, and an immaterial amount during the years ended December 31, 2020 and 2019, respectively, related to fair value hedges excluded component. Impact shown net of effect of hedged items (see Fair Value Hedges section of this Note 4 for further detail).
Offsetting Assets
Offsetting of Financial Assets and Derivative Assets
2021
Gross Amounts Not Offset
in Balance Sheet
(In millions)Gross Amount of Recognized AssetsGross Amount Offset in Balance SheetNet Amount of Assets Presented
 in Balance Sheet		Financial InstrumentsSecurities
Collateral		Cash Collateral ReceivedNet
 Amount
Derivative
  assets:
    Derivative
      assets subject to a
      master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral$858 $0 $858 $(471)$(53)$(334)$0 
    Total derivative
      assets subject to a
      master netting
      agreement or
      offsetting
      arrangement		858 0 858 (471)(53)(334)0 
    Derivative
      assets not subject
      to a master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral78 78 78 
    Total derivative
      assets not subject
      to a master netting
      agreement or
      offsetting
      arrangement		78 78 78 
    Total derivative
      assets		936 0 936 (471)(53)(334)78 
Securities lending
   and similar
   arrangements		2,124 0 2,124 0 0 (2,124)0 
    Total$3,060 $0 $3,060 $(471)$(53)$(2,458)$78 
2020
Gross Amounts Not Offset
in Balance Sheet
(In millions)Gross Amount of Recognized AssetsGross Amount Offset in Balance SheetNet Amount of Assets Presented in Balance SheetFinancial
Instruments		Securities CollateralCash Collateral ReceivedNet
 Amount
Derivative
  assets:
    Derivative
      assets subject to a
      master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral$450 $0 $450 $(295)$(73)$(76)$6 
    Total derivative
      assets subject to a
      master netting
      agreement or
      offsetting
      arrangement		450 0 450 (295)(73)(76)6 
    Derivative
      assets not subject
      to a master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral133 133 133 
    Total derivative
      assets not subject
      to a master netting
      agreement or
      offsetting
      arrangement		133 133 133 
    Total derivative
      assets		583 0 583 (295)(73)(76)139 
Securities lending
   and similar
   arrangements		940 0 940 0 0 (940)0 
    Total$1,523 $0 $1,523 $(295)$(73)$(1,016)$139 
Offsetting Liabilities
Offsetting of Financial Liabilities and Derivative Liabilities
2021
Gross Amounts Not Offset
in Balance Sheet
(In millions)Gross Amount of Recognized LiabilitiesGross Amount Offset in Balance SheetNet Amount of Liabilities Presented in Balance SheetFinancial InstrumentsSecurities CollateralCash Collateral PledgedNet
 Amount
Derivative
  liabilities:
    Derivative
      liabilities subject
      to a master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral$1,151 $0 $1,151 $(471)$(662)$(14)$4 
          OTC - cleared54 0 54 0 0 (35)19 
    Total derivative
      liabilities subject
      to a master netting
      agreement or
      offsetting
      arrangement		1,205 0 1,205 (471)(662)(49)23 
    Derivative
      liabilities not
      subject to a
      master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral414 414 414 
    Total derivative
      liabilities not
      subject to a
      master netting
      agreement or
      offsetting
      arrangement		414 414 414 
    Total derivative
      liabilities		1,619 0 1,619 (471)(662)(49)437 
Securities lending
   and similar
   arrangements		2,162 0 2,162 (2,124)0 0 38 
    Total$3,781 $0 $3,781 $(2,595)$(662)$(49)$475 
2020
Gross Amounts Not Offset
in Balance Sheet
(In millions)Gross Amount of Recognized LiabilitiesGross Amount Offset in Balance SheetNet Amount of Liabilities Presented in Balance SheetFinancial InstrumentsSecurities CollateralCash Collateral PledgedNet
 Amount
Derivative
  liabilities:
    Derivative
      liabilities subject
      to a master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral$466 $0 $466 $(295)$(43)$(69)$59 
    Total derivative
      liabilities subject
      to a master netting
      agreement or
      offsetting
      arrangement		466 0 466 (295)(43)(69)59 
    Derivative
      liabilities not
      subject to a
      master netting
      agreement or
      offsetting
      arrangement
          OTC - bilateral231 231 231 
    Total derivative
      liabilities not
      subject to a
      master netting
      agreement or
      offsetting
      arrangement		231 231 231 
    Total derivative
      liabilities		697 0 697 (295)(43)(69)290 
Securities lending
   and similar
   arrangements		964 0 964 (940)0 0 24 
    Total$1,661 $0 $1,661 $(1,235)$(43)$(69)$314 
v3.22.0.1
FAIR VALUE MEASUREMENTS (Tables)
 12 Months Ended
Dec. 31, 2021
Fair Value Disclosures [Abstract]  
Fair Value Hierarchy, Assets and Liabilities Measured on Recurring Basis The following tables present the fair value hierarchy levels of the Company's assets and liabilities that are measured and carried at fair value on a recurring basis as of December 31.
  2021
(In millions)Quoted Prices in
Active Markets
for Identical
Assets
(Level 1)		Significant
Observable
Inputs
(Level 2)		Significant
Unobservable
Inputs
(Level 3)		Total
Fair
Value
Assets:
Securities available for sale, carried at
  fair value:
Fixed maturity securities:
Government and agencies$32,532 $1,288 $0 $33,820 
Municipalities0 3,036 0 3,036 
Mortgage- and asset-backed securities0 955 291 1,246 
Public utilities0 9,558 493 10,051 
Sovereign and supranational0 1,072 43 1,115 
Banks/financial institutions0 11,546 45 11,591 
Other corporate0 37,411 426 37,837 
Total fixed maturity securities32,532 64,866 1,298 98,696 
Equity securities1,340 90 173 1,603 
Other investments1,726 0 0 1,726 
Cash and cash equivalents5,051 0 0 5,051 
Other assets:
Foreign currency swaps0 137 0 137 
Foreign currency forwards0 791 0 791 
Foreign currency options0 8 0 8 
Total other assets0 936 0 936 
Total assets$40,649 $65,892 $1,471 $108,012 
Liabilities:
Other liabilities:
Foreign currency swaps$0 $427 $0 $427 
Foreign currency forwards0 1,138 0 1,138 
Interest rate swaps0 54 0 54 
Total liabilities$0 $1,619 $0 $1,619 
  2020
(In millions)Quoted Prices in
Active Markets
for Identical
Assets
(Level 1)		Significant
Observable
Inputs
(Level 2)		Significant
Unobservable
Inputs
(Level 3)		Total
Fair
Value
Assets:
Securities available for sale, carried at
  fair value:
Fixed maturity securities:
Government and agencies$36,032 $1,318 $0 $37,350 
Municipalities0 3,018 0 3,018 
Mortgage- and asset-backed securities0 814 224 1,038 
Public utilities0 10,395 422 10,817 
Sovereign and supranational0 1,334 48 1,382 
Banks/financial institutions0 12,036 24 12,060 
Other corporate0 39,918 299 40,217 
Total fixed maturity securities36,032 68,833 1,017 105,882 
Equity securities1,095 86 102 1,283 
Other investments1,139 0 0 1,139 
Cash and cash equivalents5,141 0 0 5,141 
Other assets:
Foreign currency swaps0 47 133 180 
Foreign currency forwards0 402 0 402 
Foreign currency options0 1 0 1 
Total other assets0 450 133 583 
Total assets$43,407 $69,369 $1,252 $114,028 
Liabilities:
Other liabilities:
Foreign currency swaps$0 $81 $231 $312 
Foreign currency forwards0 385 0 385 
Total liabilities$0 $466 $231 $697 
Fair Value Hierarchy Levels of Assets and Liabilities Carried at Cost or Amortized Cost
The following tables present the carrying amount and fair value categorized by fair value hierarchy level for the Company's financial instruments that are not carried at fair value as of December 31.
2021
(In millions)Carrying
Value		Quoted Prices in
Active Markets
for Identical
Assets
(Level 1)		Significant
Observable
Inputs
(Level 2)		Significant
Unobservable
Inputs
(Level 3)		Total
Fair
Value
Assets:
Securities held to maturity,
    carried at amortized cost:
  Fixed maturity securities:
Government and agencies$21,086 $25,469 $230 $0 $25,699 
Municipalities335 0 436 0 436 
Public utilities43 0 55 0 55 
Sovereign and
   supranational		514 0 650 0 650 
Other corporate22 0 29 0 29 
Commercial mortgage and
    other loans		11,786 0 0 11,996 11,996 
Other investments (1)
22 0 22 0 22 
 Total assets$33,808 $25,469 $1,422 $11,996 $38,887 
Liabilities:
Other policyholders’ funds$7,072 $0 $0 $6,957 $6,957 
Notes payable
   (excluding leases)		7,839 0 8,280 259 8,539 
Total liabilities$14,911 $0 $8,280 $7,216 $15,496 
(1) Excludes policy loans of $236 and equity method investments of $1,858, at carrying value
2020
(In millions)Carrying
Value		Quoted Prices in
Active Markets
for Identical
Assets
(Level 1)		Significant
Observable
Inputs
(Level 2)		Significant
Unobservable
Inputs
(Level 3)		Total
Fair
Value
Assets:
Securities held to maturity,
   carried at amortized cost:
  Fixed maturity securities:
Government and agencies$23,445 $28,810 $260 $0 $29,070 
Municipalities377 0 499 0 499 
Public utilities47 0 61 0 61 
Sovereign and
   supranational		571 0 736 0 736 
Other corporate24 0 33 0 33 
Commercial mortgage and
    other loans		10,554 0 0 10,655 10,655 
Other investments (1)
26 0 26 0 26 
  Total assets$35,044 $28,810 $1,615 $10,655 $41,080 
Liabilities:
Other policyholders’ funds$7,824 $0 $0 $7,709 $7,709 
Notes payable
   (excluding leases)		7,745 0 8,396 288 8,684 
Total liabilities$15,569 $0 $8,396 $7,997 $16,393 
(1) Excludes policy loans of $260 and equity method investments of $1,004, at carrying value
Fair Value Assets Securities Carried At Fair Value Primary Pricing Sources The following tables present the pricing sources for the fair values of the Company's fixed maturity and equity securities as of December 31.
2021
(In millions)Quoted Prices in Active Markets for Identical Assets
(Level 1)		Significant Observable Inputs
(Level 2)		Significant Unobservable Inputs
(Level 3)		Total
Fair
Value
Securities available for sale, carried at fair value:
      Fixed maturity securities:
         Government and agencies:
Third party pricing vendor$32,532 $808 $0 $33,340 
Internal0 480 0 480 
               Total government and agencies32,532 1,288 0 33,820 
         Municipalities:
Third party pricing vendor0 2,222 0 2,222 
Internal0 814 0 814 
               Total municipalities0 3,036 0 3,036 
         Mortgage- and asset-backed securities:
Third party pricing vendor0 955 0 955 
Broker/other0 0 291 291 
               Total mortgage- and asset-backed securities0 955 291 1,246 
         Public utilities:
Third party pricing vendor0 4,527 0 4,527 
Internal 0 5,031 0 5,031 
Broker/other0 0 493 493 
               Total public utilities0 9,558 493 10,051 
         Sovereign and supranational:
Third party pricing vendor0 273 0 273 
Internal0 799 0 799 
Broker/other0 0 43 43 
               Total sovereign and supranational0 1,072 43 1,115 
         Banks/financial institutions:
Third party pricing vendor0 5,237 0 5,237 
Internal0 6,309 0 6,309 
Broker/other0 0 45 45 
               Total banks/financial institutions0 11,546 45 11,591 
         Other corporate:
Third party pricing vendor0 29,495 0 29,495 
Internal0 7,916 0 7,916 
Broker/other0 0 426 426 
               Total other corporate0 37,411 426 37,837 
                  Total securities available for sale$32,532 $64,866 $1,298 $98,696 
Equity securities, carried at fair value:
Third party pricing vendor$1,340 $90 $0 $1,430 
Broker/other0 0 173 173 
               Total equity securities$1,340 $90 $173 $1,603 
2020
(In millions)Quoted Prices in Active Markets
for Identical Assets
(Level 1)		Significant Observable
Inputs
(Level 2)		Significant Unobservable Inputs
(Level 3)		Total
Fair
Value
Securities available for sale, carried at fair value:
      Fixed maturity securities:
         Government and agencies:
Third party pricing vendor$36,032 $1,318 $0 $37,350 
               Total government and agencies36,032 1,318 0 37,350 
         Municipalities:
Third party pricing vendor0 3,018 0 3,018 
               Total municipalities0 3,018 0 3,018 
         Mortgage- and asset-backed securities:
Third party pricing vendor0 364 0 364 
Broker/other0 450 224 674 
               Total mortgage- and asset-backed securities0 814 224 1,038 
         Public utilities:
Third party pricing vendor0 10,395 0 10,395 
Broker/other0 0 422 422 
               Total public utilities0 10,395 422 10,817 
         Sovereign and supranational:
Third party pricing vendor0 1,334 0 1,334 
Broker/other0 0 48 48 
               Total sovereign and supranational0 1,334 48 1,382 
         Banks/financial institutions:
Third party pricing vendor0 12,036 0 12,036 
Broker/other0 0 24 24 
               Total banks/financial institutions0 12,036 24 12,060 
         Other corporate:
Third party pricing vendor0 39,886 0 39,886 
Broker/other0 32 299 331 
               Total other corporate0 39,918 299 40,217 
                  Total securities available for sale$36,032 $68,833 $1,017 $105,882 
Equity securities, carried at fair value:
Third party pricing vendor$1,095 $86 $0 $1,181 
Broker/other0 0 102 102 
               Total equity securities$1,095 $86 $102 $1,283 
Fair Value Assets Held-To-Maturity Securities Primary Pricing Sources
2021
(In millions)Quoted Prices in Active Markets for Identical Assets
(Level 1)		Significant Observable Inputs
(Level 2)		Significant Unobservable Inputs
(Level 3)		Total
Fair
 Value
Securities held to maturity, carried at amortized cost:
      Fixed maturity securities:
         Government and agencies:
Third party pricing vendor$25,469 $230 $0 $25,699 
               Total government and agencies25,469 230 0 25,699 
         Municipalities:
Third party pricing vendor0 436 0 436 
               Total municipalities0 436 0 436 
         Public utilities:
Third party pricing vendor0 55 0 55 
               Total public utilities0 55 0 55 
         Sovereign and supranational:
Third party pricing vendor0 313 0 313 
Broker/other0 337 0 337 
               Total sovereign and supranational0 650 0 650 
         Other corporate:
Third party pricing vendor0 29 0 29 
               Total other corporate0 29 0 29 
                  Total securities held to maturity$25,469 $1,400 $0 $26,869 
2020
(In millions)Quoted Prices in Active Markets
for Identical Assets
(Level 1)		Significant Observable
Inputs
(Level 2)		Significant Unobservable Inputs
(Level 3)		Total
Fair
 Value
Securities held to maturity, carried at amortized cost:
      Fixed maturity securities:
         Government and agencies:
Third party pricing vendor$28,810 $260 $0 $29,070 
               Total government and agencies28,810 260 0 29,070 
         Municipalities:
Third party pricing vendor0 499 0 499 
               Total municipalities0 499 0 499 
         Public utilities:
Third party pricing vendor0 61 0 61 
               Total public utilities0 61 0 61 
         Sovereign and supranational:
Third party pricing vendor0 736 0 736 
               Total sovereign and supranational0 736 0 736 
         Other corporate:
Third party pricing vendor0 33 0 33 
               Total other corporate0 33 0 33 
                  Total securities held to maturity$28,810 $1,589 $0 $30,399 
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation
The following tables present the changes in fair value of the Company's investments and derivatives carried at fair value classified as Level 3 as of December 31. Derivative assets and liabilities are presented as a net value.
2021
 Fixed Maturity SecuritiesEquity
Securities		Derivatives
(In millions)Mortgage-
and
Asset-
Backed
Securities		Public
Utilities		Sovereign
and
Supranational		Banks/
Financial
Institutions		Other
Corporate		 Foreign
Currency
Swaps		Total
Balance, beginning of period$224 $422 $48 $24 $299 $102 $(98)$1,021 
Net investment gains (losses) included
  in earnings		0 0 0 0 2 21 (158)(135)
Unrealized gains (losses) included in
  other comprehensive income (loss)		(25)(21)(5)(2)(11)0 (1)(65)
Purchases, issuances, sales
  and settlements:
Purchases169 167 0 23 90 41 0 490 
Issuances0 0 0 0 0 17 0 17 
Sales0 (2)(23)0 0 (8)0 (33)
Settlements0 (21)0 0 (17)0 0 (38)
Transfers into Level 30 0 23 0 84 0 0 107 
Transfers out of Level 3(77)(52)0 0 (21)0 257 107 
Balance, end of period$291 $493 $43 $45 $426 $173 $0 $1,471 
Changes in unrealized gains (losses)
  relating to Level 3 assets and liabilities
  still held at the end of the period
  included in earnings		$(24)$(23)$(4)$(2)$(27)$21 $(158)$(217)
2020
  Fixed Maturity SecuritiesEquity
Securities		Derivatives  
(In millions)Mortgage-
and
Asset-
Backed
Securities		Public
Utilities		Sovereign
and
Supranational		Banks/
Financial
Institutions		Other
Corporate		 Foreign
Currency
Swaps		Total
Balance, beginning of period$178 $224 $0 $23 $262 $80 $43 $810 
Net investment gains (losses) included
  in earnings		0 (1)0 0 0 16 (139)(124)
Unrealized gains (losses) included in
  other comprehensive income (loss)		9 19 0 0 12 0 (2)38 
Purchases, issuances, sales
  and settlements:
Purchases30 174 48 1 39 14 0 306 
Issuances0 0 0 0 0 0 0 0 
Sales0 0 0 0 0 (6)0 (6)
Settlements(2)(9)0 0 (1)0 0 (12)
Transfers into Level 39 15 0 0 2 0 0 26 
Transfers out of Level 30 0 0 0 (15)(2)0 (17)
Balance, end of period$224 $422 $48 $24 $299 $102 $(98)$1,021 
Changes in unrealized gains (losses)
  relating to Level 3 assets and liabilities
  still held at the end of the period
  included in earnings		$0 $0 $0 $0 $0 $0 $(139)$(139)
Fair Value Measurement Inputs and Valuation Techniques
Level 3 Significant Unobservable Input Sensitivity

The following tables summarize the significant unobservable inputs used in the valuation of the Company's Level 3 investments and derivatives carried at fair value as of December 31. Included in the tables are the inputs or range of possible inputs that have an effect on the overall valuation of the financial instruments.
2021
(In millions)Fair ValueValuation Technique(s)Unobservable InputRange
(Weighted Average)
Assets:
  Securities available for sale, carried at fair value:
    Fixed maturity securities:
       Mortgage- and asset-backed securities$291 Consensus pricingOffered quotesN/A
(a)
       Public utilities493 Discounted cash flowCredit spreadsN/A
(a)
       Sovereign and supranational43 Discounted cash flowHistorical volatilityN/A
(a)
       Banks/financial institutions45 Consensus pricingOffered quotesN/A
(a)
       Other corporate426 Discounted cash flowCredit spreadsN/A
(a)
  Equity securities173 Net asset valueOffered quotesN/A
(a)
            Total assets$1,471 
(a) N/A represents securities where the Company receives unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs.
2020
(In millions)Fair ValueValuation Technique(s)Unobservable InputRange
(Weighted Average)
Assets:
  Securities available for sale, carried at fair value:
    Fixed maturity securities:
       Mortgage- and asset-backed securities$224 Consensus pricingOffered quotesN/A
(a)
       Public utilities422 Discounted cash flowCredit spreadsN/A
(a)
       Sovereign and supranational48 Discounted cash flowHistorical volatilityN/A
(a)
       Banks/financial institutions24 Consensus pricingOffered quotesN/A
(a)
       Other corporate299 Discounted cash flowCredit spreadsN/A
(a)
  Equity securities102 Net asset valueOffered quotesN/A
(a)
  Other assets:
       Foreign currency swaps69 Discounted cash flowInterest rates (USD).93%-1.40%
(b)
Interest rates (JPY).05%-.43%
(c)
CDS spreads22 bps-128 bps
64 Discounted cash flowInterest rates (USD).93%-1.40%
(b)
Interest rates (JPY).05%-.43%
(c)
            Total assets$1,252 
Liabilities:
  Other liabilities:
       Foreign currency swaps$160 Discounted cash flowInterest rates (USD).93%-1.12%
(b)
Interest rates (JPY).05%-.35%
(c)
CDS spreads41 bps-140 bps
71 Discounted cash flowInterest rates (USD).93%-1.12%
(b)
Interest rates (JPY).05%-.35%
(c)
            Total liabilities$231 
(a) N/A represents securities where the Company receives unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs.
(b) Inputs derived from U.S. long-term rates to accommodate long maturity nature of the Company's swaps
(c) Inputs derived from Japan long-term rates to accommodate long maturity nature of the Company's swaps
 [1]
[1] N/A represents securities where the Company receives unadjusted broker quotes and for which there is no transparency into the providers' valuation techniques or unobservable inputs.
v3.22.0.1
DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES (Tables)
 12 Months Ended
Dec. 31, 2021
Deferred Policy Acquisition Costs Disclosures [Abstract]  
Schedule of Deferred Policy Acquisition Costs The following table presents a rollforward of deferred policy acquisition costs by segment for the years ended December 31.
  20212020
(In millions)JapanU.S.JapanU.S.
Deferred policy acquisition costs:
Balance, beginning of year$6,991 $3,450 $6,584 $3,544 
Capitalization593 470 665 486 
Amortization(653)(517)(644)(570)
Foreign currency translation and other(698)(111)386 (10)
Balance, end of year$6,233 $3,292 $6,991 $3,450 
Advertising Expense Advertising expense, which is included in insurance expenses in the consolidated statements of earnings, was as follows for the years ended December 31:
(In millions)202120202019
Advertising expense:
Aflac Japan$91 $72 $101 
Aflac U.S.138 112 118 
          Total advertising expense$229 $184 $219 
Schedule Of Depreciation And Amortization Expense
Depreciation and other amortization expenses, which are included in insurance expenses in the consolidated statements of earnings, were as follows for the years ended December 31:
(In millions)202120202019
Depreciation expense$39 $36 $40 
Other amortization expense6 5 1 
          Total depreciation and other amortization expense$45 $41 $41 
v3.22.0.1
POLICY LIABILITIES (Tables)
 12 Months Ended
Dec. 31, 2021
Insurance Loss Reserves [Abstract]  
Liability for Future Policy Benefits by Product Segment
The liability for future policy benefits as of December 31 consisted of the following:
  Liability AmountsInterest Rate Assumptions
(In millions)20212020
Health insurance
Japan$49,421 $54,659 
0.6 - 6.75
%
U.S.8,949 8,834 
3.0 - 8.0
Intercompany eliminations (1)
(456)(545)
2.0
Life insurance
Japan31,756 33,993 
0.6 - 4.5
U.S.918 842 
2.5 - 6.0
Total$90,588 $97,783 
(1) Elimination entry necessary due to recapture of a portion of policy liabilities ceded externally, as a result of the reinsurance retrocession transaction as described in Note 8 of the Notes to the Consolidated Financial Statements
Schedule of Liability for Unpaid Claims Adjustment Expense
Changes in the liability for unpaid policy claims were as follows for the years ended December 31:
(In millions)202120202019
Unpaid supplemental health claims, beginning of period$4,389 $3,968 $3,952 
Less reinsurance recoverables39 30 27 
Net balance, beginning of period4,350 3,938 3,925 
Add claims incurred during the period related to:
Current year6,969 7,179 7,216 
Prior years(860)(540)(552)
Total incurred6,109 6,639 6,664 
Less claims paid during the period on claims incurred during:
Current year4,356 4,488 4,715 
Prior years1,827 1,966 1,965 
Total paid6,183 6,454 6,680 
Effect of foreign exchange rate changes on unpaid claims(246)128 29 
Zurich acquisition0 99 0 
Net balance, end of period4,030 4,350 3,938 
Add reinsurance recoverables 37 39 30 
Unpaid supplemental health claims, end of period4,067 4,389 3,968 
Unpaid life claims, end of period769 798 691 
Total liability for unpaid policy claims$4,836 $5,187 $4,659 
v3.22.0.1
REINSURANCE (Tables)
 12 Months Ended
Dec. 31, 2021
Reinsurance Disclosures [Abstract]  
Effects of Reinsurance
The following table reconciles direct premiums and direct benefits and claims to net amounts after the effect of reinsurance which also includes the elimination of inter-segment amounts associated with affiliated reinsurance for the years ended December 31.
(In millions)202120202019
Direct earned premiums$17,857 $18,955 $19,122 
Ceded to other companies:
    Ceded Aflac Japan closed blocks(431)(466)(478)
    Other(73)(87)(69)
Assumed from other companies:
    Retrocession activities180 195 200 
    Other114 25 5 
Net earned premiums$17,647 $18,622 $18,780 
Direct benefits and claims$10,716 $12,080 $12,237 
Ceded benefits and change in reserves for future benefits:
    Ceded Aflac Japan closed blocks(379)(419)(433)
    Eliminations31 39 41 
    Other(36)(63)(57)
Assumed from other companies:
    Retrocession activities165 180 194 
    Eliminations(31)(39)(41)
    Other110 18 1 
Benefits and claims, net$10,576 $11,796 $11,942 
v3.22.0.1
NOTES PAYABLE AND LEASE OBLIGATIONS (Tables)
 12 Months Ended
Dec. 31, 2021
Debt Disclosure [Abstract]  
Schedule of Long-term Debt Instruments
A summary of notes payable and lease obligations as of December 31 follows:
(In millions)20212020
3.625% senior notes paid May 2021
$0 $698 
3.625% senior notes due November 2024
748 747 
3.25% senior notes due March 2025
448 448 
1.125% senior sustainability notes due March 2026
397 0 
2.875% senior notes due October 2026
298 298 
3.60% senior notes due April 2030
991 990 
6.90% senior notes due December 2039
221 221 
6.45% senior notes due August 2040
255 254 
4.00% senior notes due October 2046
394 394 
4.750% senior notes due January 2049
541 541 
Yen-denominated senior notes and subordinated debentures:
.300% senior notes due September 2025 (principal amount ¥12.4 billion)
107 119 
.932% senior notes due January 2027 (principal amount ¥60.0 billion)
520 578 
.500% senior notes due December 2029 (principal amount ¥12.6 billion)
109 121 
.550% senior notes due March 2030 (principal amount ¥13.3 billion)
115 127 
1.159% senior notes due October 2030 (principal amount ¥29.3 billion)
254 282 
.633% senior notes due April 2031 (principal amount ¥30.0 billion)
259 0 
.843% senior notes due December 2031 (principal amount ¥9.3 billion)
81 90 
.750% senior notes due March 2032 (principal amount ¥20.7 billion)
179 198 
.844% senior notes due April 2033 (principal amount ¥12.0 billion)
104 0 
1.488% senior notes due October 2033 (principal amount ¥15.2 billion)
131 146 
.934% senior notes due December 2034 (principal amount ¥9.8 billion)
85 94 
.830% senior notes due March 2035 (principal amount ¥10.6 billion)
91 101 
1.039% senior notes due April 2036 (principal amount ¥10.0 billion)
86 0 
1.750% senior notes due October 2038 (principal amount ¥8.9 billion)
77 85 
1.122% senior notes due December 2039 (principal amount ¥6.3 billion)
54 61 
1.264% senior notes due April 2041 (principal amount ¥10.0 billion)
86 0 
2.108% subordinated debentures due October 2047 (principal amount ¥60.0 billion)
517 575 
.963% subordinated bonds due April 2049 (principal amount ¥30.0 billion)
260 289 
1.560% senior notes due April 2051 (principal amount ¥20.0 billion)
172 0 
Yen-denominated loans:
Variable interest rate loan due September 2026 (.41% in 2021 and .43% in 2020,
  principal amount ¥5.0 billion)
43 48 
Variable interest rate loan due September 2029 (.56% in 2021 and .58% in 2020,
  principal amount ¥25.0 billion)
216 240 
Finance lease obligations payable through 202712 11 
Operating lease obligations payable through 2049105 143 
Total notes payable and lease obligations$7,956 $7,899 
Amounts in the table above are reported net of debt issuance costs and issuance premiums or discounts, if applicable, that are being amortized over the life of the notes.
Schedule of Maturities of Long Term Debt
The aggregate contractual maturities of notes payable during each of the years after December 31, 2021, are as follows:
(In millions)Total
Notes
Payable
2022$0 
20230 
2024750 
2025558 
2026743 
Thereafter5,847 
Total$7,898 
Schedule of Lease Maturities
The following table presents the contractual maturities and present value of lease liabilities as of December 31, 2021.
(In millions)Operating LeasesFinance LeasesTotal
2022$48 $4 $52 
202316 3 19 
202411 3 14 
202511 2 13 
20268 0 8 
Thereafter17 0 17 
Total lease payments$111 $12 $123 
Less: Interest6 0 6 
Present value of lease liabilities$105 $12 $117 
Lease, Cost
The following table presents the weighted average remaining lease term and weighted average discount rate for lease liabilities as of December 31.
20212020
Weighted average remaining lease term (years):
Operating leases6.86.7
Finance leases3.53.5
Weighted average discount rate:
Operating leases2.2%2.0%
Finance leases1.4%1.5%
Schedule of Line of Credit Facilities
A summary of the Company's lines of credit as of December 31, 2021 follows:
BorrowerTypeOriginal TermExpiration DateCapacityAmount OutstandingInterest Rate on Borrowed AmountMaturity PeriodCommitment FeeBusiness Purpose
Aflac Incorporated
and Aflac		uncommitted bilateral364 daysDecember 30, 2022
$100 million
$0 million
The rate quoted by the bank and agreed upon at the time of borrowing
Up to 3 months
NoneGeneral corporate purposes
Aflac Incorporatedunsecured revolving5 yearsMarch 29,
2024, or the date commitments are terminated pursuant to an event of default
¥100.0 billion
¥0.0 billion
A rate per annum equal to (a) Tokyo interbank market rate (TIBOR) plus, the alternative applicable TIBOR margin during the availability period from the closing date to the commitment termination date or (b) the TIBOR rate offered by the agent to major banks in yen for the applicable period plus, the applicable alternative TIBOR margin during the term out periodNo later than
March 29, 2024
.30% to .50%, depending on the Parent Company's debt ratings as of the date of determination
General corporate purposes, including a capital contingency plan for the operations of the Parent Company
Aflac Incorporated
and Aflac		unsecured revolving5 yearsNovember 18, 2024, or the date commitments are terminated pursuant to an event of default
$1.0 billion
$0.0 billion
A rate per annum equal to, at the Company's option, either, (a) USD LIBOR for U.S. dollar denominated borrowings or TIBOR for Japanese yen denominated borrowings, in either case adjusted for certain costs or (b) a base rate determined by reference to the highest of (1) the federal funds rate plus 1/2 of 1%, (2) the rate of interest for such day announced by Mizuho Bank, Ltd. as its prime rate, or (3) the eurocurrency rate for an interest period of one month plus 1.00%, in each case plus an applicable marginNo later than November 18, 2024
.085% to
.225%, depending on the Parent Company's debt ratings as of the date of determination
General corporate purposes, including a capital contingency plan for the operations of the Parent Company
Aflac Incorporated
and Aflac		uncommitted bilateralNone specifiedNone specified
$50 million
$0 million
A rate per annum equal to, at the Parent Company's option, either (a) a rate determined by reference to USD LIBOR for the interest period relevant to such borrowing or (b) the base rate determined by reference to the highest of (a) the lender's U.S. dollar short-term commercial loan rate, (b) the federal funds rate plus 1/2 of 1% and (c) USD one-month LIBOR plus 1%. USD LIBOR is subject to replacement with Secured Overnight Financing Rate (SOFR) under certain circumstances
Up to 3 months
NoneGeneral corporate purposes
Aflac(1)
uncommitted revolving364 daysNovember 30, 2022
$250 million
$0 million
USD three-month LIBOR plus 75 basis points per annum
3 months
NoneGeneral corporate purposes
Aflac Incorporated(1)
(Tranche 1)
uncommitted revolving364 daysNovember 25, 2022
¥50.0 billion
¥0.0 billion
Three-month TIBOR plus 70 basis points per annum
3 months
NoneGeneral corporate purposes
Aflac Incorporated(1)
(Tranche 2)
uncommitted revolving364 daysNovember 25, 2022
¥50.0 billion
¥0.0 billion
Three-month TIBOR plus 70 basis points per annum
3 months
NoneGeneral corporate purposes
Aflac New York(1)
uncommitted revolving364 daysApril 8, 2022
$25 million
$0 million
USD three-month LIBOR plus 75 basis points per annum
3 months
NoneGeneral corporate purposes
CAIC(1)
uncommitted revolving364 daysMarch 21, 2022
$15 million
$0 million
USD three-month LIBOR plus 75 basis points per annum
3 months
NoneGeneral corporate purposes
(1) Intercompany credit agreement
(continued)
BorrowerTypeOriginal TermExpiration DateCapacityAmount OutstandingInterest Rate on Borrowed AmountMaturity PeriodCommitment FeeBusiness Purpose
Tier One Insurance Company(1)
uncommitted revolving364 daysMarch 21, 2022
$0.3 million
$0 million
USD three-month LIBOR plus 75 basis points per annum
3 months
NoneGeneral corporate purposes
AGV Management Services Japan K.K.(1)
uncommitted revolving364 daysMay 2, 2022
¥500 million
¥350 million
A rate per annum equal to the short-term prime lending rates of banks appearing on the website for the Bank of Japan on the first day of the applicable periodNo later than
May 2, 2022		NoneGeneral corporate purposes
Hatch Healthcare
K.K.(1)
uncommitted revolving364 days
January 3, 2022(2)
¥900 million
¥0 million
A rate per annum equal to the short-term prime lending rates of banks appearing on the website for the Bank of Japan on the first day of the applicable periodNo later than January 3, 2022NoneGeneral corporate purposes
Hatch Insight K.K.(1)
uncommitted revolving364 days
January 3, 2022(2)
¥600 million
¥0 million
A rate per annum equal to the short-term prime lending rates of banks appearing on the website for the Bank of Japan on the first day of the applicable periodNo later than January 3, 2022NoneGeneral corporate purposes
Aflac GI Holdings LLC(1)
uncommitted revolving364 daysJuly 18, 2022
$30 million
$0 million
USD three-month LIBOR plus 75 basis points per annumNo later than
July 18, 2022		NoneGeneral corporate purposes
(1) Intercompany credit agreement
(2) Renewed in January 2022 with an expiration date of January 3, 2023
v3.22.0.1
INCOME TAXES (Tables)
 12 Months Ended
Dec. 31, 2021
Income Tax Disclosure [Abstract]  
Schedule of Components of Income Tax Expense (Benefit)
The components of income tax expense (benefit) applicable to pretax earnings for the years ended December 31 were as follows:
(In millions)ForeignU.S.Total
2021:
Current$884 $211 $1,095 
Deferred251 (349)(98)
Total income tax expense$1,135 $(138)$997 
2020:
Current$822 $(28)$794 
Deferred(28)(1,385)(1,413)
Total income tax expense$794 $(1,413)$(619)
2019:
Current$737 $69 $806 
Deferred183 152 335 
Total income tax expense$920 $221 $1,141 
Schedule of Effective Income Tax Rate Reconciliation The principal reasons for the differences and the related tax effects for the years ended December 31 were as follows:
(In millions)202120202019
Income taxes based on U.S. statutory rates$1,118 $873 $933 
Foreign rate differential0 0 229 
Valuation allowance release0 (1,411)0 
Other, net(121)(81)(21)
Income tax expense$997 $(619)$1,141 
Schedule of Income Tax Expense Benefit Intraperiod Tax Allocation
Total income tax expense for the years ended December 31 was allocated as follows:
(In millions)202120202019
Statements of earnings$997 $(619)$1,141 
Other comprehensive income (loss):
Unrealized foreign currency translation gains (losses) during
  period		15 (3)27 
Unrealized gains (losses) on fixed maturity securities:
Unrealized holding gains (losses) on fixed maturity
  securities during period		(194)223 1,532 
Reclassification adjustment for (gains) losses
  on fixed maturity securities included in net earnings		(7)33 5 
Unrealized gains (losses) on derivatives during period1 0 (3)
Pension liability adjustment during period30 (2)(18)
Total income tax expense (benefit) related to items of
  other comprehensive income (loss)		(155)251 1,543 
Total income taxes$842 $(368)$2,684 
Schedule of Deferred Tax Assets and Liabilities
The income tax effects of the temporary differences that gave rise to deferred income tax assets and liabilities as of December 31 were as follows:
(In millions)20212020
Deferred income tax liabilities:
Deferred policy acquisition costs$3,262 $3,663 
Unrealized gains and other basis differences on investments5,313 5,227 
Foreign currency gain on Aflac Japan0 70 
Premiums receivable66 112 
Policy benefit reserves3,578 3,834 
Total deferred income tax liabilities12,219 12,906 
Deferred income tax assets:
Unfunded retirement benefits7 9 
Other accrued expenses38 37 
Policy and contract claims794 868 
Foreign currency loss on Aflac Japan91 0 
Deferred compensation104 137 
Capital loss carryforwards0 12 
Depreciation230 202 
Anticipatory foreign tax credit5,883 5,972 
Deferred foreign tax credit701 647 
Other163 326 
Total deferred income tax assets8,011 8,210 
Net deferred income tax liability4,208 4,696 
Current income tax (asset) liability131 (35)
Total income tax liability$4,339 $4,661 
Summary of Income Tax Contingencies
A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows for the years ended December 31:
(In millions)2021 2020 
Balance, beginning of year$19 $17 
Additions for tax positions of prior years1   2   
Reductions for tax positions of prior years(15)  0 
Balance, end of year$5 $19 
v3.22.0.1
SHAREHOLDERS' EQUITY (Tables)
 12 Months Ended
Dec. 31, 2021
Stockholders' Equity Note [Abstract]  
Schedule of Common Stock Outstanding Roll Forward The following table is a reconciliation of the number of shares of the Company's common stock for the years ended December 31.
(In thousands of shares)202120202019
Common stock - issued:
Balance, beginning of period1,351,0181,349,3091,347,540
Exercise of stock options and issuance of restricted shares1,7211,7091,769
Balance, end of period1,352,7391,351,0181,349,309
Treasury stock:
Balance, beginning of period658,564622,516592,254
Purchases of treasury stock:
Share repurchase program43,32737,89931,994
Other437542592
Dispositions of treasury stock:
Shares issued to AFL Stock Plan(1,216)(2,021)(1,610)
Exercise of stock options(275)(121)(418)
Other(230)(251)(296)
Balance, end of period700,607658,564622,516
Shares outstanding, end of period652,132692,454726,793
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share The following table presents the approximate number of share-based awards to purchase shares, on a weighted-average basis, that were considered to be anti-dilutive and were excluded from the calculation of diluted EPS at December 31:
(In thousands)202120202019
Anti-dilutive share-based awards0 687 6 
Schedule of Weighted Average Number of Shares
The weighted-average shares used in calculating EPS for the years ended December 31 were as follows: 
(In thousands of shares)202120202019
Weighted-average outstanding shares used for calculating basic EPS673,617 713,702 742,414 
Dilutive effect of share-based awards3,112 2,490 4,016 
Weighted-average outstanding shares used for calculating diluted EPS676,729 716,192 746,430 
Changes in Accumulated Other Comprehensive Income (Loss) The tables below are reconciliations of accumulated other comprehensive income by component for the years ended December 31.
Changes in Accumulated Other Comprehensive Income
2021
(In millions)Unrealized Foreign
Currency Translation
Gains (Losses)		Unrealized
Gains (Losses)
on Fixed Maturity Securities		Unrealized
Gains (Losses)
on Derivatives		Pension
Liability
Adjustment		Total
Balance at December 31, 2020$(1,109)$10,361 $(34)$(284)$8,934 
Other comprehensive
   income (loss) before
   reclassification 		(904)(735)(1)90 (1,550)
Amounts reclassified from
   accumulated other
   comprehensive income
  (loss)		0 (24)5 28 9 
Net current-period other
   comprehensive
   income (loss)		(904)(759)4 118 (1,541)
Balance at December 31, 2021$(2,013)$9,602 $(30)$(166)$7,393 
All amounts in the table above are net of tax.
2020
(In millions)Unrealized Foreign
Currency Translation
Gains (Losses)		Unrealized
Gains (Losses)
on Fixed Maturity Securities		Unrealized
Gains (Losses)
on Derivatives		Pension Liability AdjustmentTotal
Balance at December 31, 2019$(1,623)$8,548 $(33)$(277)$6,615 
Cumulative effect of change
   in accounting principle -
   ASU 2019-04		0 848 0 0 848 
Balance at January 1, 2020$(1,623)$9,396 $(33)$(277)$7,463 
Other comprehensive
   income (loss) before
   reclassification		514 839 (1)(30)1,322 
Amounts reclassified from
   accumulated other
   comprehensive income
  (loss)		0 126 0 23 149 
Net current-period other
   comprehensive
   income (loss)		514 965 (1)(7)1,471 
Balance at December 31, 2020$(1,109)$10,361 $(34)$(284)$8,934 
All amounts in the table above are net of tax.
2019
(In millions)Unrealized Foreign
Currency Translation
Gains (Losses)		Unrealized
Gains (Losses)
on Fixed Maturity Securities		Unrealized
Gains (Losses)
on Derivatives		Pension Liability AdjustmentTotal
Balance at December 31, 2018$(1,847)$4,234 $(24)$(212)$2,151 
Other comprehensive
   income (loss) before
   reclassification		224 4,327 (9)(76)4,466 
Amounts reclassified from
   accumulated other
   comprehensive income
  (loss)		0 (13)0 11 (2)
Net current-period other
   comprehensive
   income (loss)		224 4,314 (9)(65)4,464 
Balance at December 31, 2019$(1,623)$8,548 $(33)$(277)$6,615 
All amounts in the table above are net of tax.
Reclassification out of Accumulated Other Comprehensive Income
The tables below summarize the amounts reclassified from each component of accumulated other comprehensive income based on source for the years ended December 31.

Reclassifications Out of Accumulated Other Comprehensive Income
(In millions)2021
Details about Accumulated Other Comprehensive Income ComponentsAmount Reclassified from Accumulated Other Comprehensive IncomeAffected Line Item in the
Statements of Earnings
Unrealized gains (losses) on available-for-sale
   securities		$31 Net investment gains (losses)
(7)
Tax (expense) or benefit(1)
$24 Net of tax
Unrealized gains (losses) on derivatives$(5)Net investment gains (losses)
(1)Net investment income
(6)Total before tax
1 
Tax (expense) or benefit(1)
$(5)Net of tax
Amortization of defined benefit pension items:
       Actuarial gains (losses)$(35)
Acquisition and operating expenses(2)
Prior service (cost) credit0 
Acquisition and operating expenses(2)
7 
Tax (expense) or benefit(1)
$(28)Net of tax
Total reclassifications for the period$(9)Net of tax
(1) Based on 21% tax rate
(2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 14 for additional details).
(In millions)2020
Details about Accumulated Other Comprehensive Income ComponentsAmount Reclassified from Accumulated Other Comprehensive IncomeAffected Line Item in the
Statements of Earnings
Unrealized gains (losses) on available-for-sale
   securities		$(159)Net investment gains (losses)
33 
Tax (expense) or benefit(1)
$(126)Net of tax
Amortization of defined benefit pension items:
       Actuarial gains (losses)$(32)
Acquisition and operating expenses(2)
Prior service (cost) credit3 
Acquisition and operating expenses(2)
6 
Tax (expense) or benefit(1)
$(23)Net of tax
Total reclassifications for the period$(149)Net of tax
(1) Based on 21% tax rate
(2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 14 for additional details).

(In millions)2019
Details about Accumulated Other Comprehensive Income ComponentsAmount Reclassified from Accumulated Other Comprehensive IncomeAffected Line Item in the
Statements of Earnings
Unrealized gains (losses) on available-for-sale
   securities		$18 Net investment gains (losses)
(5)
Tax (expense) or benefit(1)
$13 Net of tax
Amortization of defined benefit pension items:
       Actuarial gains (losses)$(15)
Acquisition and operating expenses(2)
       Prior service (cost) credit0 
Acquisition and operating expenses(2)
4 
Tax (expense) or benefit(1)
$(11)Net of tax
Total reclassifications for the period$2 Net of tax
(1) Based on 26% blended tax rate
(2) These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 14 for additional details).
v3.22.0.1
SHARE-BASED COMPENSATION (Tables)
 12 Months Ended
Dec. 31, 2021
Share-based Payment Arrangement [Abstract]  
Schedule of Expense Recognized in Connection with Share Based Awards
The following table presents the impact of the expense recognized in connection with share-based awards for the periods ended December 31.
(In millions, except for per-share amounts)202120202019
Impact on earnings from continuing operations$65 $61 $59 
Impact on earnings before income taxes65 61 59 
Impact on net earnings51 48 46 
Impact on net earnings per share:
Basic$.08 $.07 $.06 
Diluted.08 .07 .06 
Schedule of Share-based Compensation, Stock Options, Activity
The following table summarizes stock option activity under the employee stock option plan.
(In thousands of shares)Stock
Option
Shares		Weighted-Average
Exercise Price
Per Share
Outstanding at December 31, 20185,330 $28.54 
Granted in 20190 0.00 
Canceled in 2019(40)27.28 
Exercised in 2019(1,584)25.97 
Outstanding at December 31, 20193,706 29.65 
Granted in 202059 35.75 
Canceled in 2020(82)26.31 
Exercised in 2020(638)27.82 
Outstanding at December 31, 20203,045 30.25 
Granted in 20210 0.00 
Canceled in 2021(4)16.93 
Exercised in 2021(896)28.45 
Outstanding at December 31, 20212,145 $31.02 
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable
(In thousands of shares)202120202019
Shares exercisable, end of year2,145 2,986 3,553 
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions The following table presents the assumptions used in valuing options granted, if applicable, during the years ended December 31.
202120202019
Expected term (years)7.96.07.0
Expected volatility25.6 %24.4 %18.0 %
Annual forfeiture rate3.8 3.9 3.9 
Risk-free interest rate1.0 2.0 2.9 
Dividend yield3.0 3.3 2.2 
Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range
The following table summarizes information about stock options outstanding and exercisable at December 31, 2021.
(In thousands of shares)Options OutstandingOptions Exercisable
Range of
Exercise Prices
Per Share		Stock Option
Shares
Outstanding		Wgtd.-Avg.
Remaining
Contractual
Life (Yrs.)		Wgtd.-Avg.
Exercise
Price
Per Share		Stock Option
Shares
Exercisable		Wgtd.-Avg.
Exercise
Price
Per Share
$0.00 -$24.75 336 0.7$24.09 336 $24.09 
24.75 -28.97 370 3.928.85 370 28.85 
28.97 -31.21 718 2.830.74 718 30.74 
31.21 -36.21 572 4.734.36 572 34.36 
36.21 -44.59 149 5.840.57 149 40.57 
$0.00 -$44.59 2,145 3.4$31.02 2,145 $31.02 
Schedule of Cash Proceeds Received from Share-based Payment Awards
The following table summarizes stock option activity during the years ended December 31.
(In millions)202120202019
Total intrinsic value of options exercised$21 $11 $38 
Cash received from options exercised26 18 40 
Tax benefit realized as a result of options exercised and
  restricted stock releases		17 18 34 
Schedule of Share-based Payment Award, Performance Based Restricted Stock, Valuation Assumptions
Key assumptions used to value PBRS granted during 2021 follows:
(In millions)2021
Expected volatility (based on Aflac Inc. and peer group historical daily stock price) 36.75 %
Expected life from grant date (years)2.9
Risk-free interest rate (based on U.S. Treasury yields at the date of grant)0.18 %
Schedule of Nonvested Restricted Stock Units Activity
The value of restricted stock awards and restricted stock units is based on the fair market value of the Company's common stock at the date of grant. The following table summarizes restricted stock activity during the years ended December 31. 
(In thousands of shares)SharesWeighted-Average
Grant-Date
Fair Value
Per  Share
Restricted stock at December 31, 20183,407 $36.52 
Granted in 2019 (1)
1,070 49.68 
Canceled in 2019 (1)
(39)41.60 
Vested in 2019 (1)
(1,723)32.50 
Restricted stock at December 31, 2019 (1)
2,715 43.74 
Granted in 20201,544 45.88 
Canceled in 2020(119)49.27 
Vested in 2020(1,560)35.23 
Restricted stock at December 31, 20202,580 48.57 
Granted in 20211,496 47.87 
Canceled in 2021(148)49.00 
Vested in 2021(1,371)45.80 
Restricted stock at December 31, 20212,557 $49.38 
v3.22.0.1
STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS (Tables)
 12 Months Ended
Dec. 31, 2021
Insurance [Abstract]  
Schedule of Capital and Surplus Based on Statutory Accounting Practices
The table below represents statutory capital and surplus based on statutory accounting practices for the Company’s U.S. life insurance subsidiaries as of December 31.
(In millions)20212020
Aflac$2,627 $2,088 
CAIC244 271 
TOIC57 61 
Aflac New York360 352 
Schedule of Net Income (Loss) Based on Statutory Accounting Practices
The table below represents net income (loss) based on statutory accounting practices for the Company’s U.S. life insurance subsidiaries as of December 31.
(In millions)202120202019
Aflac$1,146 $872 $864 
CAIC(30)1 (16)
TOIC(27)(24)(2)
Aflac New York83 75 75 
Profit Remittances Disclosure Profits remitted by Aflac Japan to the Parent Company were as follows for the years ended December 31:
  
In DollarsIn Yen
(In millions of dollars and billions of yen)202120202019202120202019
Profit remittances$2,138 $1,215 $2,070 ¥236.7 ¥129.8 ¥225.2 
v3.22.0.1
BENEFIT PLANS (Tables)
 12 Months Ended
Dec. 31, 2021
Schedule of Net Funded Status
Information with respect to the Company's benefit plans' assets and obligations as of December 31 was as follows:
Pension BenefitsOther
JapanU.S.Postretirement Benefits
(In millions)202120202021202020212020
Projected benefit obligation:
      Benefit obligation, beginning of year$473 $436 $1,204 $1,058 $42 $39 
      Service cost23 24 28 29 0 0 
      Interest cost6 5 32 34 1 1 
      Actuarial (gain) loss(9)(6)(50)106 (2)6 
      Benefits and expenses paid(15)(12)(28)(23)(5)(4)
      Effect of foreign exchange
         rate changes		(46)26 0 0 0 0 
               Benefit obligation, end of year432 473 1,186 1,204 36 42 
Plan assets:
      Fair value of plan assets,
         beginning of year		416 344 824 644 0 0 
      Actual return on plan assets14 21 81 96 0 0 
      Employer contributions44 41 8 107 5 4 
      Benefits and expenses paid(15)(12)(28)(23)(5)(4)
      Effect of foreign exchange
         rate changes		(44)22 0 0 0 0 
               Fair value of plan assets,
                  end of year		415 416 885 824 0 0 
Funded status of the plans(1)
$(17)$(57)$(301)$(380)$(36)$(42)
Amounts recognized in accumulated other
    comprehensive income:
      Net actuarial (gain) loss$50 $74 $158 $278 $10 $15 
      Prior service (credit) cost0 (1)(2)(2)0 0 
               Total included in accumulated
                  other comprehensive income		$50 $73 $156 $276 $10 $15 
Accumulated benefit obligation$346 $425 $1,010 $1,017   N/AN/A
(1) Recognized in other liabilities in the consolidated balance sheets
Information for Pension Plans with Accumulated Benefit Obligation in Excess of Plan Assets
Information for Pension Plans with an Accumulated Benefit Obligation in Excess of Plan Assets
Pension Benefits
JapanU.S.
(In millions)2021202020212020
Accumulated benefit obligation $346 $425 $1,010 $1,017 
Fair value of plan assets415 416 885 824 
Information for Pension Plans with a Projected Benefit Obligation in Excess of Plan Assets
Information for Pension Plans with a Projected Benefit Obligation in Excess of Plan Assets
Pension Benefits
Japan (1)
U.S.(2)
(In millions)2021202020212020
Projected benefit obligation $432 $473 $1,186 $1,204 
Fair value of plan assets415 416 885 824 
(1) The net amount of projected benefit obligation and plan assets for the underfunded (including unfunded) Japan pension plan was $17 and $57 at December 31, 2021 and 2020, respectively, and was classified as liabilities on the statement of financial position.
(2) The net amount of projected benefit obligation and plan assets for the underfunded (including unfunded) U.S. pension plan was $301 and $380 at December 31, 2021 and 2020, respectively, and was classified as liabilities on the statement of financial position.
Schedule of Assumptions Used
Pension BenefitsOther
JapanU.S.Postretirement Benefits
202120202019202120202019202120202019
Weighted-average
  actuarial assumptions:		                    
Discount rate - net periodic benefit cost.75%.75%1.25%2.68%3.25%4.25%2.68%3.25%4.25%
Discount rate - benefit
  obligations		.94.75.752.942.683.25  2.942.683.25  
Expected long-term return
  on plan assets		2.002.002.005.756.006.25N/AN/AN/A
Rate of compensation
  increase		N/AN/AN/A4.004.004.00N/AN/AN/A
Health care cost trend ratesN/AN/AN/AN/AN/AN/A5.80
(2)
6.30
(2)
7.50
(2)
(2) For the years 2021, 2020 and 2019, the health care cost trend rates are expected to trend down to 3.7% in 52 years, 3.7% in 53 years, and 3.8% in 54 years, respectively.
Schedule of Net Benefit Costs Total net periodic benefit cost includes the following components:
Pension BenefitsOther
JapanU.S.Postretirement Benefits
(In millions)202120202019202120202019202120202019
Service cost$23 $24 $22 $28 $29 $23 $0 $0 $0 
Interest cost6 5 7 32 34 20 1 1 1 
Expected return on plan assets(8)(7)(6)(41)(35)(29)0 0 0 
Amortization of net actuarial loss2 4 4 30 26 10 3 2 1 
Amortization of prior service cost0 (1)0 0 (2)0 0 0 0 
Net periodic (benefit) cost$23 $25 $27 $49 $52 $24 $4 $3 $2 
Schedule of Amounts Recognized in Other Comprehensive Income (Loss)
The following table summarizes the amounts recognized in other comprehensive loss (income) for the years ended December 31:
Pension BenefitsOther
JapanU.S.Postretirement Benefits
(In millions)202120202019202120202019202120202019
Net actuarial loss (gain)$(22)$(14)$1 $(90)$45 $95 $(2)$5 $4 
Amortization of net actuarial loss(2)(4)(4)(30)(26)(10)(3)(2)(1)
Amortization of prior
  service cost 		1 1 0 0 2 0 0 0 0 
     Total$(23)$(17)$(3)$(120)$21 $85 $(5)$3 $3 
Schedule of Expected Benefit Payments
The following table provides expected benefit payments, which reflect expected future service, as appropriate.
Pension BenefitsOther
(In millions)JapanU.S.Postretirement Benefits
2022$17 $32 $5 
202314 32 5 
202416 34 5 
202517 35 4 
202617 37 4 
2027-203188 237 9 
Schedule of Allocation of Plan Assets Asset allocation targets as of December 31, 2021 were as follows:
Japan PensionU.S. Pension
Domestic equities5 %40 %
International equities21 20 
Fixed income securities66 40 
Other8 0 
     Total100 %100 %
Plan Assets  
Fair Value, Assets Measured on Recurring Basis
The following table presents the fair value of Aflac Japan's pension plan assets that are measured at fair value on a recurring basis as of December 31. All of these assets are classified as Level 2 in the fair value hierarchy.
(In millions)20212020
Japan pension plan assets:
     Equities:
        Japanese equity securities$21 $20 
        International equity securities86 88 
     Fixed income securities:
        Japanese bonds22 23 
        International bonds252 249 
     Insurance contracts34 36 
        Total$415 $416 
The following table presents the fair value of Aflac U.S.'s pension plan assets that are measured at fair value on a recurring basis as of December 31. All of these assets are classified as Level 1 in the fair value hierarchy.
(In millions)20212020
U.S. pension plan assets:
     Mutual funds:
        Large cap equity funds$297 $234 
        Mid cap equity funds25 24 
        Real estate equity funds0 19 
        International equity funds208 136 
        Fixed income bond funds346 237 
     Aflac Incorporated common stock7 5 
     Cash and cash equivalents2 169 
        Total$885 $824 
v3.22.0.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Summary of Signficant Accounting Policies - Additional Information (Detail)
$ in Millions
 12 Months Ended
Dec. 31, 2021
USD ($)
segment
Dec. 31, 2020
USD ($)
Dec. 31, 2019
USD ($)
Jan. 01, 2021
USD ($)
Jan. 01, 2020
USD ($)
Jan. 01, 2019
USD ($)
Dec. 31, 2018
USD ($)
Significant Accounting Policies [Line Items]              
Number of reportable insurance business segments | segment 2            
Goodwill $ 268 $ 269          
Stockholders' Equity Attributable to Parent 33,253 33,559 $ 28,959       $ 23,462
Accumulated Other Comprehensive Income (Loss), Net of Tax $ 7,393 $ 8,934 $ 6,615       2,151
Aflac Japan              
Significant Accounting Policies [Line Items]              
Percentage of the Company's total revenues 69.00% 68.00% 69.00%        
Percentage of the Company's total assets 82.00% 83.00%          
Accounting Standards Update 2019-04              
Significant Accounting Policies [Line Items]              
New accounting pronouncement or change in accounting principle effect of adoption unrealized gain loss net of tax reclassification to accumulated other comprehensive income         $ 848    
Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjustment              
Significant Accounting Policies [Line Items]              
Stockholders' Equity Attributable to Parent [1]     $ 848        
Accumulated Other Comprehensive Income (Loss), Net of Tax     848        
Accounting Standards Update 2016-02              
Significant Accounting Policies [Line Items]              
New accounting pronouncement or change in accounting principle, cumulative effect of change on liabilities           $ 134  
Accounting Standards Update 2016-13 | Cumulative effect, period of adoption, adjustment              
Significant Accounting Policies [Line Items]              
Stockholders' Equity Attributable to Parent [1]     (56)        
Accounting Standards Update 2018-12 | Maximum | Cumulative effect, period of adoption, adjustment | Pro Forma              
Significant Accounting Policies [Line Items]              
Accumulated Other Comprehensive Income (Loss), Net of Tax       $ (20,000)      
Accounting Standards Update 2018-12 | Lower Limit | Cumulative effect, period of adoption, adjustment | Pro Forma              
Significant Accounting Policies [Line Items]              
Accumulated Other Comprehensive Income (Loss), Net of Tax       $ (18,000)      
Accumulated other comprehensive income (loss)              
Significant Accounting Policies [Line Items]              
Stockholders' Equity Attributable to Parent $ 7,393 $ 8,934 6,615       2,151
Accumulated other comprehensive income (loss) | Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjustment              
Significant Accounting Policies [Line Items]              
Stockholders' Equity Attributable to Parent [1]     848        
Accumulated other comprehensive income (loss) | Accounting Standards Update 2016-13 | Cumulative effect, period of adoption, adjustment              
Significant Accounting Policies [Line Items]              
Stockholders' Equity Attributable to Parent [1]     0        
Retained earnings              
Significant Accounting Policies [Line Items]              
Stockholders' Equity Attributable to Parent $ 41,381 $ 37,984 34,291       $ 31,788
Retained earnings | Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjustment              
Significant Accounting Policies [Line Items]              
Stockholders' Equity Attributable to Parent [1]     0        
Retained earnings | Accounting Standards Update 2016-13 | Cumulative effect, period of adoption, adjustment              
Significant Accounting Policies [Line Items]              
Stockholders' Equity Attributable to Parent     $ (56) [1]   $ 56    
[1] See Note 1 of the Notes to the Consolidated Financial Statements for the adoption of accounting guidance on January 1, 2020.
v3.22.0.1
BUSINESS SEGMENT AND FOREIGN INFORMATION - Additional Information (Details)
$ in Millions
 12 Months Ended
Dec. 31, 2021
USD ($)
segment
Dec. 31, 2020
USD ($)
Segment Reporting Information [Line Items]    
Number of reportable insurance business segments | segment 2  
Total receivables related to Aflac Japan's operations $ 693 $ 796
Aflac Japan    
Segment Reporting Information [Line Items]    
Total receivables related to Aflac Japan's operations $ 195 $ 201
Percentage of total receivables related to Aflac Japan's operations 28.10% 25.20%
Maximum | Machinery and equipment    
Segment Reporting Information [Line Items]    
Property, Plant and Equipment, Useful Life 20 years  
Maximum | Building    
Segment Reporting Information [Line Items]    
Property, Plant and Equipment, Useful Life 50 years  
Maximum | Furniture and fixtures    
Segment Reporting Information [Line Items]    
Property, Plant and Equipment, Useful Life 20 years  
v3.22.0.1
BUSINESS SEGMENT AND FOREIGN INFORMATION - Operations by Segment - Revenues (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Segment Reporting, Revenue Reconciling Item [Line Items]      
Net earned premiums, principally supplemental health insurance $ 17,647 $ 18,622 $ 18,780
Total revenues 22,106 22,147 22,307
Total adjusted revenues 21,589 22,320 22,256
Net investment gains (losses) [1],[2],[3],[4] 517 (173) 51
Life insurance      
Segment Reporting, Revenue Reconciling Item [Line Items]      
Net earned premiums, principally supplemental health insurance 2,956 3,253 3,445
Aflac Japan      
Segment Reporting, Revenue Reconciling Item [Line Items]      
Net earned premiums, principally supplemental health insurance 11,853 12,670 12,772
Adjusted net investment income [1],[3] 3,031 2,659 2,496
Other income (loss) 41 42 45
Total revenues 14,925 15,371 15,313
Hedge costs 76 206 257
Net interest cash flows from derivatives (33) 9 (17)
Aflac Japan | Cancer      
Segment Reporting, Revenue Reconciling Item [Line Items]      
Net earned premiums, principally supplemental health insurance 5,829 6,119 6,031
Aflac Japan | Medical and other health      
Segment Reporting, Revenue Reconciling Item [Line Items]      
Net earned premiums, principally supplemental health insurance 3,400 3,596 3,582
Aflac Japan | Life insurance      
Segment Reporting, Revenue Reconciling Item [Line Items]      
Net earned premiums, principally supplemental health insurance 2,624 2,955 3,159
Aflac U.S.      
Segment Reporting, Revenue Reconciling Item [Line Items]      
Net earned premiums, principally supplemental health insurance 5,614 5,758 5,808
Adjusted net investment income [4] 754 705 720
Other income (loss) 121 102 22
Total revenues 6,489 6,565 6,550
Net interest cash flows from derivatives 2 3  
Aflac U.S. | Cancer      
Segment Reporting, Revenue Reconciling Item [Line Items]      
Net earned premiums, principally supplemental health insurance 1,216 1,275 1,309
Aflac U.S. | Life insurance      
Segment Reporting, Revenue Reconciling Item [Line Items]      
Net earned premiums, principally supplemental health insurance 332 298 286
Aflac U.S. | Accident and disability      
Segment Reporting, Revenue Reconciling Item [Line Items]      
Net earned premiums, principally supplemental health insurance 2,524 2,614 2,665
Aflac U.S. | Other health      
Segment Reporting, Revenue Reconciling Item [Line Items]      
Net earned premiums, principally supplemental health insurance 1,542 1,571 1,548
Corporate and other      
Segment Reporting, Revenue Reconciling Item [Line Items]      
Total revenues [2],[5] 175 384 393
Hedge income 57 97 89
All other      
Segment Reporting, Revenue Reconciling Item [Line Items]      
Net earned premiums, principally supplemental health insurance 180 $ 194 $ 200
Income (Loss) from federal historic rehabilitation and solar tax credit investments (138)    
Federal historic rehabilitation and solar tax credits, amount $ 115    
[1] Amortized hedge costs of $76, $206 and $257 in 2021, 2020 and 2019, respectively, related to certain foreign currency exposure management strategies have been reclassified from net investment gains (losses) and reported as a deduction from net investment income when analyzing operations.
[2] Amortized hedge income of $57, $97 and $89 in 2021, 2020 and 2019, respectively, related to certain foreign currency exposure management strategies has been reclassified from net investment gains (losses) and reported as an increase to net investment income when analyzing operations.
[3] Net interest cash flows from derivatives associated with certain investment strategies of $(33), $9, and $(17) in 2021, 2020, and 2019, respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income when analyzing operations.
[4] Net interest cash flows from derivatives associated with certain investment strategies of $2 and $3 in 2021 and 2020, respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income when analyzing operations.
[5] The change in value of federal historic rehabilitation and solar investments in partnerships of $138 in 2021 is included as a reduction to net investment income. Tax credits on these investments of $115 in 2021 has been recorded as an income tax benefit in the consolidated statement of earnings. See Note 3 of the Notes to the Consolidated Financial Statements for additional information on these investments.
v3.22.0.1
BUSINESS SEGMENT AND FOREIGN INFORMATION - Operations by Segment - Pretax Earnings (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]      
Pretax adjusted earnings [1] $ 4,934 $ 4,416 $ 4,461
Net investment gains (losses) [2],[3],[4],[5],[6] 462 (229) (15)
Other income (loss) (74) (28) (1)
Earnings before income taxes 5,322 4,159 4,445
Income taxes applicable to pretax adjusted earnings 915 864 1,147
Effect of foreign currency translation on after tax adjusted earnings (38) 31 15
Interest expense on debt 170 167 135
Aflac Japan      
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]      
Pretax adjusted earnings [3],[5] 3,754 3,263 3,261
Hedge costs 76 206 257
Net interest cash flows from derivatives (33) 9 (17)
Aflac U.S.      
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]      
Pretax adjusted earnings [6] 1,478 1,268 1,272
Net interest cash flows from derivatives 2 3  
Corporate and other      
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]      
Pretax adjusted earnings [2],[4],[7] (298) (115) (72)
Hedge income 57 97 89
Gain (loss) on change in fair value of derivative, interest rate component 55 $ 56 $ 66
All other      
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]      
Income (Loss) from federal historic rehabilitation and solar tax credit investments (138)    
Federal historic rehabilitation and solar tax credits, amount $ 115    
[1] Includes $170, $167 and $135 of interest expense on debt in 2021, 2020 and 2019, respectively.
[2] A gain of $55, $56 and $66 in 2021, 2020 and 2019, respectively, related to the interest rate component of the change in fair value of foreign currency swaps on notes payable has been reclassified from net investment gains (losses) and included in adjusted earnings when analyzing operations.
[3] Amortized hedge costs of $76, $206 and $257 in 2021, 2020 and 2019, respectively, related to certain foreign currency exposure management strategies have been reclassified from net investment gains (losses) and reported as a deduction from net investment income when analyzing operations.
[4] Amortized hedge income of $57, $97 and $89 in 2021, 2020 and 2019, respectively, related to certain foreign currency exposure management strategies has been reclassified from net investment gains (losses) and reported as an increase to net investment income when analyzing operations.
[5] Net interest cash flows from derivatives associated with certain investment strategies of $(33), $9, and $(17) in 2021, 2020, and 2019, respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income when analyzing operations.
[6] Net interest cash flows from derivatives associated with certain investment strategies of $2 and $3 in 2021 and 2020, respectively, have been reclassified from net investment gains (losses) and included in adjusted earnings as a component of net investment income when analyzing operations.
[7] The change in value of federal historic rehabilitation and solar investments in partnerships of $138 in 2021 is included as a reduction to net investment income. Tax credits on these investments of $115 in 2021 has been recorded as an income tax benefit in the consolidated statement of earnings. See Note 3 of the Notes to the Consolidated Financial Statements for additional information on these investments.
v3.22.0.1
BUSINESS SEGMENT AND FOREIGN INFORMATION - Operations by Segment - Assets (Detail) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Segment Reporting, Asset Reconciling Item [Line Items]    
Assets $ 157,542 $ 165,086
Aflac Japan    
Segment Reporting, Asset Reconciling Item [Line Items]    
Assets 128,536 137,271
Aflac U.S.    
Segment Reporting, Asset Reconciling Item [Line Items]    
Assets 23,106 22,864
Corporate and other    
Segment Reporting, Asset Reconciling Item [Line Items]    
Assets $ 5,900 $ 4,951
v3.22.0.1
BUSINESS SEGMENT AND FOREIGN INFORMATION - Yen/Dollar Exchange Rates Used (Detail)
$ in Millions
 12 Months Ended
Dec. 31, 2021
USD ($)
¥ / $
Dec. 31, 2020
USD ($)
¥ / $
Dec. 31, 2019
USD ($)
¥ / $
Segment Reporting, Other Significant Reconciling Item [Line Items]      
Weighted-average yen/dollar exchange rate | ¥ / $ [1] 109.79 106.86 109.07
Yen percent strengthening (weakening) (2.70%) 2.10% 1.20%
Exchange effect on pretax operating earnings (in millions) $ (47) $ 38 $ 20
Yen/dollar exchange rate at December 31 | ¥ / $ [1] 115.02 103.50  
Yen percent strengthening (weakening) (10.00%) 5.90%  
Exchange effect on total assets      
Segment Reporting, Other Significant Reconciling Item [Line Items]      
Exchange effect $ (9,635) $ 7,970  
Exchange effect on total liabilities      
Segment Reporting, Other Significant Reconciling Item [Line Items]      
Exchange effect $ (7,566) $ 7,870  
[1] Rates are based on the published MUFG Bank, Ltd. telegraphic transfer middle rate (TTM)
v3.22.0.1
BUSINESS SEGMENT AND FOREIGN INFORMATION - Information on Transfers of Funds from Aflac Japan (Detail)
$ in Millions, ¥ in Billions
 12 Months Ended
Dec. 31, 2021
USD ($)
Dec. 31, 2021
JPY (¥)
Dec. 31, 2020
USD ($)
Dec. 31, 2020
JPY (¥)
Dec. 31, 2019
USD ($)
Dec. 31, 2019
JPY (¥)
Segment Reporting [Abstract]            
Management fees $ 59   $ 71   $ 75  
Allocated expenses 0   0   4  
Profit remittances 2,138 ¥ 236.7 1,215 ¥ 129.8 2,070 ¥ 225.2
Total transfers from Aflac Japan $ 2,197   $ 1,286   $ 2,149  
v3.22.0.1
BUSINESS SEGMENT AND FOREIGN INFORMATION - Classes of Property and Equipment (Detail) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Property and equipment:    
Land $ 168 $ 168
Buildings 491 523
Equipment 542 566
Total property and equipment 1,201 1,257
Less accumulated depreciation 663 656
Net property and equipment $ 538 $ 601
v3.22.0.1
INVESTMENTS - Components of Net Investment Income (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Schedule of Investment Income, Reported Amounts, by Category [Line Items]      
Gross investment income $ 4,036 $ 3,850 $ 3,755
Less investment expenses 218 212 177
Net investment income 3,818 3,638 3,578
All other      
Schedule of Investment Income, Reported Amounts, by Category [Line Items]      
Net investment income (73) 80 105
Income (Loss) from federal historic rehabilitation and solar tax credit investments (138)    
Federal historic rehabilitation and solar tax credits, amount 115    
Fixed maturity securities      
Schedule of Investment Income, Reported Amounts, by Category [Line Items]      
Gross investment income 3,068 3,113 3,141
Equity securities      
Schedule of Investment Income, Reported Amounts, by Category [Line Items]      
Gross investment income 35 29 37
Commercial mortgage and other loans      
Schedule of Investment Income, Reported Amounts, by Category [Line Items]      
Gross investment income 570 545 468
Other investments      
Schedule of Investment Income, Reported Amounts, by Category [Line Items]      
Gross investment income 356 145 53
Short-term investments and cash equivalents      
Schedule of Investment Income, Reported Amounts, by Category [Line Items]      
Gross investment income $ 7 $ 18 $ 56
v3.22.0.1
INVESTMENTS - Available-for-Sale Debt Securities (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost $ 85,369 $ 91,630
Allowance for Credit Losses 0 38
Gross Unrealized Gains 13,566 14,771
Gross Unrealized Losses 239 481
Fair Value 98,696 105,882
Yen-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 51,160 56,049
Allowance for Credit Losses 0 0
Gross Unrealized Gains 6,994 8,420
Gross Unrealized Losses 167 198
Fair Value 57,987 64,271
Dollar-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 34,209 35,581
Allowance for Credit Losses 0 38
Gross Unrealized Gains 6,572 6,351
Gross Unrealized Losses 72 283
Fair Value 40,709 41,611
Japan government and agencies | Yen-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 30,335 32,959
Allowance for Credit Losses 0 0
Gross Unrealized Gains 3,343 4,182
Gross Unrealized Losses 61 52
Fair Value 33,617 37,089
U.S. government and agencies | Dollar-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 196 245
Allowance for Credit Losses 0 0
Gross Unrealized Gains 8 16
Gross Unrealized Losses 1 0
Fair Value 203 261
Municipalities    
Debt Securities, Available-for-Sale [Line Items]    
Fair Value 3,036 3,018
Municipalities | Yen-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 1,192 1,324
Allowance for Credit Losses 0 0
Gross Unrealized Gains 322 374
Gross Unrealized Losses 5 5
Fair Value 1,509 1,693
Municipalities | Dollar-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 1,340 1,154
Allowance for Credit Losses 0 0
Gross Unrealized Gains 189 173
Gross Unrealized Losses 2 2
Fair Value 1,527 1,325
Mortgage- and asset-backed securities    
Debt Securities, Available-for-Sale [Line Items]    
Fair Value 1,246 1,038
Mortgage- and asset-backed securities | Yen-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 300 342
Allowance for Credit Losses 0 0
Gross Unrealized Gains 19 27
Gross Unrealized Losses 1 1
Fair Value 318 368
Mortgage- and asset-backed securities | Dollar-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 897 667
Allowance for Credit Losses 0 0
Gross Unrealized Gains 33 8
Gross Unrealized Losses 2 5
Fair Value 928 670
Public utilities    
Debt Securities, Available-for-Sale [Line Items]    
Fair Value 10,051 10,817
Public utilities | Yen-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 4,462 4,777
Allowance for Credit Losses 0 0
Gross Unrealized Gains 906 1,096
Gross Unrealized Losses 2 1
Fair Value 5,366 5,872
Public utilities | Dollar-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 3,781 4,013
Allowance for Credit Losses 0 0
Gross Unrealized Gains 909 947
Gross Unrealized Losses 5 15
Fair Value 4,685 4,945
Sovereign and supranational    
Debt Securities, Available-for-Sale [Line Items]    
Fair Value 1,115 1,382
Sovereign and supranational | Yen-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 760 981
Allowance for Credit Losses 0 0
Gross Unrealized Gains 82 108
Gross Unrealized Losses 0 0
Fair Value 842 1,089
Sovereign and supranational | Dollar-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 222 232
Allowance for Credit Losses 0 0
Gross Unrealized Gains 57 64
Gross Unrealized Losses 6 3
Fair Value 273 293
Banks/financial institutions    
Debt Securities, Available-for-Sale [Line Items]    
Fair Value 11,591 12,060
Banks/financial institutions | Yen-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 6,963 7,552
Allowance for Credit Losses 0 0
Gross Unrealized Gains 787 886
Gross Unrealized Losses 72 102
Fair Value 7,678 8,336
Banks/financial institutions | Dollar-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 3,169 2,973
Allowance for Credit Losses 0 0
Gross Unrealized Gains 747 758
Gross Unrealized Losses 3 7
Fair Value 3,913 3,724
Other corporate    
Debt Securities, Available-for-Sale [Line Items]    
Fair Value 37,837 40,217
Other corporate | Yen-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 7,148 8,114
Allowance for Credit Losses 0 0
Gross Unrealized Gains 1,535 1,747
Gross Unrealized Losses 26 37
Fair Value 8,657 9,824
Other corporate | Dollar-denominated    
Debt Securities, Available-for-Sale [Line Items]    
Amortized Cost 24,604 26,297
Allowance for Credit Losses 0 38
Gross Unrealized Gains 4,629 4,385
Gross Unrealized Losses 53 251
Fair Value $ 29,180 $ 30,393
v3.22.0.1
INVESTMENTS - Held-to-Maturity Debt Securities (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost $ 22,008 $ 24,474
Allowance for Credit Losses 8 10
Net Carrying Amount 22,000 [1] 24,464
Gross Unrealized Gains 4,869 5,935
Gross Unrealized Losses 0 0
Fair Value 26,869 30,399
Yen-denominated    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 22,008 24,474
Allowance for Credit Losses 8 10
Net Carrying Amount 22,000 24,464
Gross Unrealized Gains 4,869 5,935
Gross Unrealized Losses 0 0
Fair Value 26,869 30,399
Japan government and agencies | Yen-denominated    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 21,089 23,448
Allowance for Credit Losses 3 3
Net Carrying Amount 21,086 23,445
Gross Unrealized Gains 4,613 5,625
Gross Unrealized Losses 0 0
Fair Value 25,699 29,070
Municipalities    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 335 377
Fair Value 436 499
Municipalities | Yen-denominated    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 335 377
Allowance for Credit Losses 0 0
Net Carrying Amount 335 377
Gross Unrealized Gains 101 122
Gross Unrealized Losses 0 0
Fair Value 436 499
Public utilities    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 43 47
Fair Value 55 61
Public utilities | Yen-denominated    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 44 48
Allowance for Credit Losses 1 1
Net Carrying Amount 43 47
Gross Unrealized Gains 12 14
Gross Unrealized Losses 0 0
Fair Value 55 61
Sovereign and supranational    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 514 571
Fair Value 650 736
Sovereign and supranational | Yen-denominated    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 518 577
Allowance for Credit Losses 4 6
Net Carrying Amount 514 571
Gross Unrealized Gains 136 165
Gross Unrealized Losses 0 0
Fair Value 650 736
Other corporate    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 22 24
Fair Value 29 33
Other corporate | Yen-denominated    
Schedule of Held-to-maturity Securities [Line Items]    
Amortized Cost 22 24
Allowance for Credit Losses 0 0
Net Carrying Amount 22 24
Gross Unrealized Gains 7 9
Gross Unrealized Losses 0 0
Fair Value $ 29 $ 33
[1] Net of allowance for credit losses
v3.22.0.1
INVESTMENTS - Equity Securities (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Equity Securities, FV-NI [Line Items]    
Fair Value $ 1,603 $ 1,283
Yen-denominated    
Equity Securities, FV-NI [Line Items]    
Fair Value 744 680
Dollar-denominated    
Equity Securities, FV-NI [Line Items]    
Fair Value 817 603
Other currencies    
Equity Securities, FV-NI [Line Items]    
Fair Value $ 42 $ 0
v3.22.0.1
INVESTMENTS - Contractual and Economic Maturities of Investments in Fixed Maturities (Detail) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Available for sale:    
Due in one year or less [1] $ 984  
Due after one year through five years [1] 8,145  
Due after five years through 10 years [1] 13,288  
Due after 10 years [1] 61,755  
Mortgage- and asset-backed securities [1] 1,197  
Total fixed maturity securities available for sale [1] 85,369  
Held to maturity:    
Due in one year or less [1] 0  
Due after one year through five years [1] 44  
Due after five years through 10 years [1] 10,121  
Due after 10 years [1] 11,835  
Mortgage- and asset-backed securities [1] 0  
Total fixed maturity securities held to maturity 22,000 [1] $ 24,464
Available for sale:    
Due in one year or less 1,015  
Due after one year through five years 8,782  
Due after five years through 10 years 15,491  
Due after 10 years 72,163  
Mortgage- and asset-backed securities 1,245  
Available for sale, fixed maturity securities 98,696 105,882
Held to maturity:    
Due in one year or less 0  
Due after one year through five years 48  
Due after five years through 10 years 11,772  
Due after 10 years 15,049  
Mortgage- and asset-backed securities 0  
Held to maturity, fixed maturity securities, fair value $ 26,869 $ 30,399
[1] Net of allowance for credit losses
v3.22.0.1
INVESTMENTS - Investment Exposures Individually Exceeded 10% of Shareholders' Equity (Detail) - Japan National Government - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Summary of Investment Holdings [Line Items]    
Credit Rating [1] A+ A+
Fair Value [1] $ 57,862 $ 64,657
Amortized Cost [1] $ 50,186 $ 55,153
[1] Japan Government Bonds (JGBs) or JGB-backed securities
v3.22.0.1
INVESTMENTS - Information Regarding Pretax Net Gains and Losses From Investments (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Gain (Loss) on Securities [Line Items]      
Loan loss reserves [1] $ 0 $ 0 $ (18)
Total net investment gains (losses) 468 (270) (135)
Credit Losses      
Fixed maturity securities available for sale 38 (38) 0
Fixed maturity securities held to maturity 1 1 0
Commercial mortgage and other loans 6 (93) 0
Impairment losses [2] (20) (49) (13)
Loan commitments 4 (21) 0
Reinsurance recoverables and other (2) 0 0
Total credit losses 27 (200) (13)
Derivatives and Other      
Derivative gains (losses) (805) 399 (174)
Foreign currency gains (losses) 1,069 (568) (62)
Derivatives and other      
Gain (Loss) on Securities [Line Items]      
Total net investment gains (losses) 264 (169) (236)
Fixed maturity securities      
Gain (Loss) on Securities [Line Items]      
Gross gains from sales 64 31 115
Gross losses from sales (52) (47) (68)
Foreign currency gains (losses) on sales and redemptions 1 (69) (16)
Total net investment gains (losses) 13 (85) 31
Equity securities      
Gain (Loss) on Securities [Line Items]      
Total net investment gains (losses) $ 164 $ 184 $ 101
[1] U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only
[2] Includes OTTI losses in 2019
v3.22.0.1
INVESTMENTS - Information Regarding Changes in Unrealized Gains and Losses from Investments (Detail) - USD ($)
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Changes in unrealized gains (losses):      
Changes in unrealized gains (losses) $ (960,000,000) $ 2,399,000,000 $ 5,852,000,000
Financing Receivable, Troubled Debt Restructuring 0    
Fixed maturity securities | Available-for-sale securities      
Changes in unrealized gains (losses):      
Changes in unrealized gains (losses) $ (960,000,000) $ 2,399,000,000 $ 5,852,000,000
v3.22.0.1
INVESTMENTS - Net Effect on Shareholders' Equity of Unrealized Gains and Losses from Investment Securities (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Investments [Abstract]    
Unrealized gains (losses) on securities available for sale $ 13,330 $ 14,290
Deferred income taxes (3,728) (3,929)
Shareholders' equity, unrealized gains (losses) on fixed maturity securities $ 9,602 $ 10,361
v3.22.0.1
INVESTMENTS - Fair Value and Gross Unrealized Losses for Securities That Have Been in Continuous Unrealized Loss Position (Details) - Fixed maturity securities - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total $ 239 $ 481
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 42 184
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 7,914 10,781
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 2,948 6,902
12 months or longer Unrealized Losses 4,966 3,879
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 197 297
Yen-denominated | Japan government and agencies    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 61 52
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 3 52
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 2,868 2,604
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 445 2,604
12 months or longer Unrealized Losses 2,423 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 58 0
Yen-denominated | Municipalities    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 5 5
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 0 4
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 187 183
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 53 169
12 months or longer Unrealized Losses 134 14
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 5 1
Yen-denominated | Mortgage- and asset-backed securities    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 1 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 0 1
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 33 37
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 0 37
12 months or longer Unrealized Losses 33 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 1 0
Yen-denominated | Public utilities    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 2 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 0 1
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 26 135
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 0 135
12 months or longer Unrealized Losses 26 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 2 0
Yen-denominated | Banks/financial institutions    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 72 102
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 16 36
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 2,074 1,809
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 1,011 765
12 months or longer Unrealized Losses 1,063 1,044
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 56 66
Yen-denominated | Other corporate    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 26 37
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 4 13
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 541 613
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 274 290
12 months or longer Unrealized Losses 267 323
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 22 24
Dollar-denominated | U.S. government and agencies    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 1  
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 1  
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 1  
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 0  
12 months or longer Unrealized Losses 1  
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 0  
Dollar-denominated | Municipalities    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 2 2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 2 2
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 82 94
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 79 94
12 months or longer Unrealized Losses 3 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 0 0
Dollar-denominated | Mortgage- and asset-backed securities    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 2 5
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 2 5
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 278 360
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 278 360
12 months or longer Unrealized Losses 0 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 0 0
Dollar-denominated | Public utilities    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 5 15
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 2 7
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 130 326
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 70 208
12 months or longer Unrealized Losses 60 118
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 3 8
Dollar-denominated | Sovereign and supranational    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 6 3
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 1 3
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 37 39
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 6 39
12 months or longer Unrealized Losses 31 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 5 0
Dollar-denominated | Banks/financial institutions    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 3 7
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 3 1
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 292 82
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 274 44
12 months or longer Unrealized Losses 18 38
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 0 6
Dollar-denominated | Other corporate    
Investments, Unrealized Loss Position [Line Items]    
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss, Total 53 251
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 8 59
Debt Securities, Available-for-sale, Unrealized Loss Position, Total 1,365 4,499
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months 458 2,157
12 months or longer Unrealized Losses 907 2,342
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss $ 45 $ 192
v3.22.0.1
INVESTMENTS - Commercial Mortgage and Other Loans by Portfolio Segment (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
 [1]
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 11,960 $ 10,734  
Percent of total commercial mortgage and other loans 100.00% 100.00%  
Allowance for credit losses $ (174) $ (180)  
Total net commercial mortgage and other loans 11,786 10,554  
Commercial mortgage loans      
Participating Mortgage Loans [Line Items]      
Financing Receivable, before Allowance for Credit Loss 1,904    
Prior $ 674    
Weighted average debt-service coverage ratio 2.45    
Commercial mortgage loans | Prior      
Participating Mortgage Loans [Line Items]      
Weighted average debt-service coverage ratio 2.30    
Commercial mortgage loans | 2017      
Participating Mortgage Loans [Line Items]      
Weighted average debt-service coverage ratio 2.75    
Commercial mortgage loans | Loan to Value Ratio, Zero to Fifty-nine Point Nine-nine Percent      
Participating Mortgage Loans [Line Items]      
Financing Receivable, before Allowance for Credit Loss $ 1,645    
Prior $ 535    
Weighted average debt-service coverage ratio 2.53    
Commercial mortgage loans | Loan to Value Ratio, Sixty to Sixty-nine Point Nine-nine Percent      
Participating Mortgage Loans [Line Items]      
Financing Receivable, before Allowance for Credit Loss $ 234    
Prior $ 114    
Weighted average debt-service coverage ratio 1.92    
Commercial mortgage loans | Loan to Value Ratio, Seventy to Seventy-nine Point Nine-nine Percent      
Participating Mortgage Loans [Line Items]      
Financing Receivable, before Allowance for Credit Loss $ 25    
Prior $ 25    
Weighted average debt-service coverage ratio 1.65    
Commercial mortgage loans | Loan to Value Ratio Eighty Percent and Above      
Participating Mortgage Loans [Line Items]      
Financing Receivable, before Allowance for Credit Loss $ 0    
Prior $ 0    
Weighted average debt-service coverage ratio 0.00    
Transitional real estate loans      
Participating Mortgage Loans [Line Items]      
Financing Receivable, before Allowance for Credit Loss $ 5,359    
Prior 0    
Transitional real estate loans | Loan to Value Ratio, Zero to Fifty-nine Point Nine-nine Percent      
Participating Mortgage Loans [Line Items]      
Financing Receivable, before Allowance for Credit Loss 1,489    
Prior 0    
Transitional real estate loans | Loan to Value Ratio, Sixty to Sixty-nine Point Nine-nine Percent      
Participating Mortgage Loans [Line Items]      
Financing Receivable, before Allowance for Credit Loss 2,111    
Prior 0    
Transitional real estate loans | Loan to Value Ratio, Seventy to Seventy-nine Point Nine-nine Percent      
Participating Mortgage Loans [Line Items]      
Financing Receivable, before Allowance for Credit Loss 1,663    
Prior 0    
Transitional real estate loans | Loan to Value Ratio Eighty Percent and Above      
Participating Mortgage Loans [Line Items]      
Financing Receivable, before Allowance for Credit Loss 96    
Prior 0    
Transitional real estate loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 5,359 $ 5,294  
Percent of total commercial mortgage and other loans 44.70% 49.30%  
Allowance for credit losses $ (68) $ (63) $ (22)
Commercial mortgage loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 1,904 $ 1,720  
Percent of total commercial mortgage and other loans 15.90% 16.00%  
Allowance for credit losses $ (10) $ (32) (3)
Middle market loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 4,697 $ 3,720  
Percent of total commercial mortgage and other loans 39.40% 34.70%  
Allowance for credit losses $ (96) $ (85) $ (20)
Office | Transitional real estate loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 2,001 $ 2,115  
Percent of total commercial mortgage and other loans 16.70% 19.70%  
Office | Commercial mortgage loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 398 $ 401  
Percent of total commercial mortgage and other loans 3.30% 3.70%  
Retail | Transitional real estate loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 267 $ 125  
Percent of total commercial mortgage and other loans 2.20% 1.20%  
Retail | Commercial mortgage loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 332 $ 340  
Percent of total commercial mortgage and other loans 2.80% 3.20%  
Apartments/Multi-Family | Transitional real estate loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 1,893 $ 1,782  
Percent of total commercial mortgage and other loans 15.80% 16.60%  
Apartments/Multi-Family | Commercial mortgage loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 649 $ 588  
Percent of total commercial mortgage and other loans 5.40% 5.50%  
Industrial | Transitional real estate loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 94 $ 85  
Percent of total commercial mortgage and other loans 0.80% 0.80%  
Industrial | Commercial mortgage loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 525 $ 391  
Percent of total commercial mortgage and other loans 4.40% 3.60%  
Hospitality | Transitional real estate loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 876 $ 1,106  
Percent of total commercial mortgage and other loans 7.30% 10.30%  
Other | Transitional real estate loans      
Participating Mortgage Loans [Line Items]      
Commercial mortgage and other loans, gross $ 228 $ 81  
Percent of total commercial mortgage and other loans 1.90% 0.70%  
[1] U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only
v3.22.0.1
INVESTMENTS - Transitional Real Estate Loans by Key Credit Quality Indicators (Details) - Transitional real estate loans
$ in Millions
Dec. 31, 2021
USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 $ 2,400
2020 353
2019 1,654
2018 829
2017 123
Prior 0
Total Financing Receivable 5,359
Loan to Value Ratio, Zero to Fifty-nine Point Nine-nine Percent  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 866
2020 36
2019 502
2018 85
2017 0
Prior 0
Total Financing Receivable 1,489
Loan to Value Ratio, Sixty to Sixty-nine Point Nine-nine Percent  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 620
2020 136
2019 840
2018 465
2017 50
Prior 0
Total Financing Receivable 2,111
Loan to Value Ratio, Seventy to Seventy-nine Point Nine-nine Percent  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 846
2020 153
2019 312
2018 279
2017 73
Prior 0
Total Financing Receivable 1,663
Loan to Value Ratio Eighty Percent and Above  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 68
2020 28
2019 0
2018 0
2017 0
Prior 0
Total Financing Receivable $ 96
v3.22.0.1
INVESTMENTS - Commercial Mortgage Loans by Key Credit Quality Indicator (Details) - Commercial mortgage loans
$ in Millions
Dec. 31, 2021
USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 $ 340
2020 47
2019 608
2018 167
2017 68
Prior 674
Total Financing Receivable $ 1,904
Weighted average debt-service coverage ratio 2.45
2021  
Financing Receivable, Credit Quality Indicator [Line Items]  
Weighted average debt-service coverage ratio 2.83
2020  
Financing Receivable, Credit Quality Indicator [Line Items]  
Weighted average debt-service coverage ratio 1.93
2019  
Financing Receivable, Credit Quality Indicator [Line Items]  
Weighted average debt-service coverage ratio 2.46
2018  
Financing Receivable, Credit Quality Indicator [Line Items]  
Weighted average debt-service coverage ratio 2.29
2017  
Financing Receivable, Credit Quality Indicator [Line Items]  
Weighted average debt-service coverage ratio 2.75
Prior  
Financing Receivable, Credit Quality Indicator [Line Items]  
Weighted average debt-service coverage ratio 2.30
Loan to Value Ratio, Zero to Fifty-nine Point Nine-nine Percent  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 $ 306
2020 47
2019 522
2018 167
2017 68
Prior 535
Total Financing Receivable $ 1,645
Weighted average debt-service coverage ratio 2.53
Loan to Value Ratio, Sixty to Sixty-nine Point Nine-nine Percent  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 $ 34
2020 0
2019 86
2018 0
2017 0
Prior 114
Total Financing Receivable $ 234
Weighted average debt-service coverage ratio 1.92
Loan to Value Ratio, Seventy to Seventy-nine Point Nine-nine Percent  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 $ 0
2020 0
2019 0
2018 0
2017 0
Prior 25
Total Financing Receivable $ 25
Weighted average debt-service coverage ratio 1.65
Loan to Value Ratio Eighty Percent and Above  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 $ 0
2020 0
2019 0
2018 0
2017 0
Prior 0
Total Financing Receivable $ 0
Weighted average debt-service coverage ratio 0.00
v3.22.0.1
INVESTMENTS - Middle Market Loans by Key Credit Quality Indicators (Details) - Middle market loans
$ in Millions
Dec. 31, 2021
USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 $ 1,210
2020 903
2019 909
2018 499
2017 326
Prior 182
Revolving Loans 668
Total Financing Receivable 4,697
BBB Credit Rating  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 136
2020 67
2019 43
2018 24
2017 0
Prior 0
Revolving Loans 72
Total Financing Receivable 342
BB Credit Rating  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 353
2020 332
2019 234
2018 134
2017 42
Prior 24
Revolving Loans 275
Total Financing Receivable 1,394
B Credit Rating  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 721
2020 482
2019 568
2018 267
2017 179
Prior 111
Revolving Loans 246
Total Financing Receivable 2,574
CCC Credit Rating  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 0
2020 22
2019 64
2018 60
2017 79
Prior 47
Revolving Loans 74
Total Financing Receivable 346
CC Credit Rating  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 0
2020 0
2019 0
2018 14
2017 26
Prior 0
Revolving Loans 1
Total Financing Receivable 41
C and Lower Credit Rating  
Financing Receivable, Credit Quality Indicator [Line Items]  
2021 0
2020 0
2019 0
2018 0
2017 0
Prior 0
Revolving Loans 0
Total Financing Receivable $ 0
v3.22.0.1
INVESTMENTS - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Allowance for Loan Losses by Portfolio Segment [Roll Forward]      
Balance, beginning of period $ (180)    
(Addition to) release of allowance for credit losses [1] 0 $ 0 $ 18
Balance, end of period (174) (180)  
Transitional real estate loans      
Allowance for Loan Losses by Portfolio Segment [Roll Forward]      
Balance, beginning of period (63) (22) [1]  
Transition impact to retained earnings     (2)
(Addition to) release of allowance for credit losses (5) (39)  
Write-offs, net of recoveries 0 0  
Change in foreign exchange 0    
Balance, end of period (68) (63) (22) [1]
Commercial mortgage loans      
Allowance for Loan Losses by Portfolio Segment [Roll Forward]      
Balance, beginning of period (32) (3) [1]  
Transition impact to retained earnings     (8)
(Addition to) release of allowance for credit losses 22 (21)  
Write-offs, net of recoveries 0 0  
Change in foreign exchange 0    
Balance, end of period (10) (32) (3) [1]
Middle market loans      
Allowance for Loan Losses by Portfolio Segment [Roll Forward]      
Balance, beginning of period (85) (20) [1]  
Transition impact to retained earnings     (33)
(Addition to) release of allowance for credit losses (11) (41)  
Write-offs, net of recoveries 0 9  
Change in foreign exchange 0    
Balance, end of period (96) (85) (20) [1]
Held-to-maturity securities      
Allowance for Loan Losses by Portfolio Segment [Roll Forward]      
Balance, beginning of period (10) 0 [1]  
Transition impact to retained earnings     (10)
(Addition to) release of allowance for credit losses 1 0  
Write-offs, net of recoveries 0 0  
Change in foreign exchange 1    
Balance, end of period (8) (10) 0 [1]
Available-for-sale securities      
Allowance for Loan Losses by Portfolio Segment [Roll Forward]      
Balance, beginning of period (38) 0 [1]  
Transition impact to retained earnings     0
(Addition to) release of allowance for credit losses 26 (75)  
Write-offs, net of recoveries 12 37  
Change in foreign exchange 0    
Balance, end of period 0 (38) 0 [1]
Reinsurance recoverables      
Allowance for Loan Losses by Portfolio Segment [Roll Forward]      
Balance, beginning of period (12) 0 [1]  
Transition impact to retained earnings     (11)
(Addition to) release of allowance for credit losses (2) (1)  
Write-offs, net of recoveries 0 0  
Change in foreign exchange 1    
Balance, end of period $ (13) $ (12) $ 0 [1]
[1] U.S. GAAP guidance adopted as of January 1, 2020 has superseded these losses, included for comparative purposes only
v3.22.0.1
INVESTMENTS - Other Investments (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Investment [Line Items]    
Other investments $ 3,842 $ 2,429
Policy loans    
Investment [Line Items]    
Other investments 236 260
Short-term investments    
Investment [Line Items]    
Other investments [1] 1,726 1,139
Limited partnerships    
Investment [Line Items]    
Other investments 1,858 1,004
Other Investments    
Investment [Line Items]    
Other investments $ 22 $ 26
[1] Includes securities lending collateral
v3.22.0.1
INVESTMENTS - Investments in Consolidated Variable Interest Entities (Detail) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Variable Interest Entity [Line Items]    
Available for sale, fixed maturity securities, amortized cost $ 85,369 $ 91,630
Available for sale, fixed maturity securities 98,696 105,882
Commercial mortgage and other loans 11,786 10,554
Commercial mortgage and other loans, fair value 11,996 10,655
Other investments 3,842 2,429
Asset derivatives 936 583
Assets, fair value 108,012 114,028
Liability derivatives 1,619 697
Liabilities 124,289 131,527
Liabilities, fair value 1,619 697
Variable Interest Entity, Consolidated    
Variable Interest Entity [Line Items]    
Available for sale, fixed maturity securities, amortized cost [1] 3,264 3,487
Available for sale, fixed maturity securities 4,490 4,596
Commercial mortgage and other loans [1] 9,740 8,964
Commercial mortgage and other loans, fair value 9,910 9,040
Other investments [1],[2] 1,535 826
Other investments, fair value [2] 1,535 826
Asset derivatives, amortized cost 78 133 [1],[3]
Asset derivatives [3] 78 133
Assets, amortized cost [1] 14,617 13,410
Assets, fair value 16,013 14,595
Liability derivatives, amortized cost [1],[3] 414 231
Liability derivatives [3] 414 231
Liabilities [1] 414 231
Liabilities, fair value $ 414 $ 231
[1] Net of allowance for credit losses
[2] Consists entirely of alternative investments in limited partnerships
[3] Consists entirely of derivatives
v3.22.0.1
INVESTMENTS - Investments in Variable Interest Entities Not Consolidated (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Variable Interest Entity [Line Items]    
Available for sale, fixed maturity securities, amortized cost $ 85,369 $ 91,630
Available for sale, fixed maturity securities 98,696 105,882
Securities held to maturity, fixed maturities, amortized cost 22,008 24,474
Held to maturity, fixed maturity securities, fair value 26,869 30,399
Other investments 3,842 2,429
Assets, fair value 108,012 114,028
Variable Interest Entity, Not Consolidated    
Variable Interest Entity [Line Items]    
Available for sale, fixed maturity securities, amortized cost 4,779 5,477
Available for sale, fixed maturity securities 5,864 6,767
Other investments [1] 323 178
Other investments, fair value [1] 323 178
Assets, amortized cost 5,102 5,655
Assets, fair value $ 6,187 $ 6,945
[1] Consists entirely of alternative investments in limited partnerships
v3.22.0.1
INVESTMENTS - Securities Lending Transactions Accounted for as Secured Borrowings (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred $ 2,162 $ 964
Gross amount of recognized liabilities for securities lending 2,162 964
Japan government and agencies    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred 920 0
Public utilities    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred 40 57
Sovereign and supranational    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred 2 3
Banks/financial institutions    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred 88 63
Other corporate    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred 1,112 841
Maturity Overnight and Continuous    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred [1] 1,242 964
Maturity Overnight and Continuous | Japan government and agencies    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred [1] 0 0
Maturity Overnight and Continuous | Public utilities    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred [1] 40 57
Maturity Overnight and Continuous | Sovereign and supranational    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred [1] 2 3
Maturity Overnight and Continuous | Banks/financial institutions    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred [1] 88 63
Maturity Overnight and Continuous | Other corporate    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred [1] 1,112 841
Maturity up to 30 Days    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred 920 0
Maturity up to 30 Days | Japan government and agencies    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred 920 0
Maturity up to 30 Days | Public utilities    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred 0 0
Maturity up to 30 Days | Sovereign and supranational    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred 0 0
Maturity up to 30 Days | Banks/financial institutions    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred 0 0
Maturity up to 30 Days | Other corporate    
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]    
Securities Loaned, Including Not Subject to Master Netting Arrangement and Assets other than Securities Transferred $ 0 $ 0
[1] The related loaned security, under the Company's U.S. securities lending program, can be returned to the Company at the transferee's discretion; therefore, they are classified as Overnight and Continuous.
v3.22.0.1
INVESTMENTS - Additional Information (Details)
 3 Months Ended 12 Months Ended
Mar. 31, 2020
USD ($)
Dec. 31, 2021
USD ($)
investment
Dec. 31, 2019
USD ($)
investment
Dec. 31, 2020
USD ($)
Jan. 01, 2020
USD ($)
Schedule of Investments [Line Items]          
Held to maturity securities transferred to available for sale securities, number of investments | investment   0 0    
Equity securities, FV-NI, unrealized gain (loss)   $ 141,000,000      
Transitional real estate loan commitments   665,000,000      
Commercial mortgage loan commitments   0      
Middle market loan program unfunded amount   11,000,000   $ 25,000,000  
Middle market loan commitments   $ 1,400,000,000      
Percentage that the lending policy requires that the fair value of the securities and/or unrestricted cash received as collateral be of the fair value of the loaned securities   102.00%      
Percentage that the lending policy requires that the fair value of the unrestricted cash received as collateral be of the fair value of the loaned securities   100.00%      
Fair value of debt securities on deposit with regulatory authorities in the United States and Japan   $ 17,000,000      
Securities held to maturity, fixed maturities, amortized cost   22,008,000,000   24,474,000,000  
Available for sale, fixed maturity securities, amortized cost   85,369,000,000   91,630,000,000  
Middle market loan commitment increase during period $ 2,200,000,000        
Off-balance sheet, credit loss, liability   31,000,000   35,000,000  
Securities received as collateral   6,800,000,000   6,700,000,000  
Financing receivable, troubled debt restructuring   0      
Available-for-sale, allowance for credit losses   0   38,000,000  
Limited partnerships investment commitments   1,800,000,000      
Repurchase agreements and repurchase to maturity transactions outstanding   $ 0   0  
Accounting Standards Update 2019-04          
Schedule of Investments [Line Items]          
New accounting pronouncement or change in accounting principle effect of adoption unrealized gain loss net of tax reclassification to accumulated other comprehensive income         $ 848,000,000
Revision of Prior Period, Accounting Standards Update, Adjustment | Accounting Standards Update 2019-04          
Schedule of Investments [Line Items]          
Securities held to maturity, fixed maturities, amortized cost     $ (6,900,000,000)    
Available for sale, fixed maturity securities, amortized cost     $ 6,900,000,000    
California | Commercial mortgage and transitional real estate loans | Mortgages          
Schedule of Investments [Line Items]          
Concentration Risk, Percentage   21.00%      
Texas | Commercial mortgage and transitional real estate loans | Mortgages          
Schedule of Investments [Line Items]          
Concentration Risk, Percentage   12.00%      
Florida | Commercial mortgage and transitional real estate loans | Mortgages          
Schedule of Investments [Line Items]          
Concentration Risk, Percentage   8.00%      
Yen-denominated          
Schedule of Investments [Line Items]          
Securities held to maturity, fixed maturities, amortized cost   $ 22,008,000,000   24,474,000,000  
Available for sale, fixed maturity securities, amortized cost   51,160,000,000   56,049,000,000  
Available-for-sale, allowance for credit losses   0   0  
Japan government and agencies | Zero-credit-loss expectation          
Schedule of Investments [Line Items]          
Securities held to maturity, fixed maturities, amortized cost   20,900,000,000      
Japan government and agencies | Yen-denominated          
Schedule of Investments [Line Items]          
Securities held to maturity, fixed maturities, amortized cost   21,089,000,000   23,448,000,000  
Available for sale, fixed maturity securities, amortized cost   30,335,000,000   32,959,000,000  
Available-for-sale, allowance for credit losses   $ 0   $ 0  
v3.22.0.1
DERIVATIVE INSTRUMENTS - Additional Information (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Line Items]    
Maximum Length of Time Hedged in Cash Flow Hedge 5 years  
Derivative, notional amount $ 43,454 $ 58,656
Derivative, net liability position, aggregate fair value 904 $ 268
Additional collateral, aggregate fair value 193  
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred (5)  
Interest rate swaps | Senior notes    
Derivative Instruments and Hedging Activities Disclosure [Line Items]    
Derivative, notional amount $ 2,300  
v3.22.0.1
DERIVATIVE INSTRUMENTS - Summary of Balance Sheet Classification of Derivative Fair Value Amounts, as well as Gross Asset and Liability Fair Value Amounts (Detail) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Derivatives, Fair Value [Line Items]    
Derivative, notional amount $ 43,454 $ 58,656
Derivative asset, fair value, gross asset including not subject to master netting arrangement 936 583
Derivative liability, fair value, gross liability including not subject to master netting arrangement 1,619 697
Asset derivatives fair value 858 450
Liability derivatives fair value 1,205 466
Cash flow hedges    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 18 18
Asset derivatives fair value 0 0
Liability derivatives fair value 2 1
Cash flow hedges | Foreign currency swaps | Variable Interest Entity    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 18 18
Asset derivatives fair value 0 0
Liability derivatives fair value 2 1
Fair value hedges    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 8,891 8,929
Asset derivatives fair value 5 2
Liability derivatives fair value 5 0
Fair value hedges | Foreign currency forwards    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 62 64
Asset derivatives fair value 0 2
Liability derivatives fair value 5 0
Fair value hedges | Foreign currency options    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 8,829 8,865
Asset derivatives fair value 5 0
Liability derivatives fair value 0 0
Net investment hedge    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 6,945 7,037
Asset derivatives fair value 341 15
Liability derivatives fair value 0 84
Net investment hedge | Foreign currency forwards    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 4,996 5,010
Asset derivatives fair value 341 14
Liability derivatives fair value 0 84
Net investment hedge | Foreign currency options    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 1,949 2,027
Asset derivatives fair value 0 1
Liability derivatives fair value 0 0
Non-qualifying strategies    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 27,600 42,672
Asset derivatives fair value 590 566
Liability derivatives fair value 1,612 612
Non-qualifying strategies | Foreign currency swaps | Variable Interest Entity    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 3,151 2,857
Asset derivatives fair value 78 133
Liability derivatives fair value 412 230
Non-qualifying strategies | Foreign currency swaps | Consolidated Entity Excluding Variable Interest Entities (VIE)    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 2,250 2,250
Asset derivatives fair value 59 47
Liability derivatives fair value 13 81
Non-qualifying strategies | Foreign currency forwards    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 15,953 26,528
Asset derivatives fair value 450 386
Liability derivatives fair value 1,133 301
Non-qualifying strategies | Foreign currency options    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 2,746 11,037
Asset derivatives fair value 3 0
Liability derivatives fair value 0 0
Non-qualifying strategies | Interest rate swaps    
Derivatives, Fair Value [Line Items]    
Derivative, notional amount 3,500 0
Asset derivatives fair value 0 0
Liability derivatives fair value $ 54 $ 0
v3.22.0.1
DERIVATIVE INSTRUMENTS - Gains (Losses) Recognized on Fair Value Hedging Relationships (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]      
Total gains (losses) recognized for derivatives $ (33) $ (23) $ (66)
Gains (losses) on derivatives excluded from effectiveness testing [1] (25) (16) (80)
Gain (losses) on derivatives included in effectiveness testing [2] (8) (7) 14
Gains (losses) recognized for hedged items [2] 10 8 (12)
Net realized gains (losses) recognized for fair value hedge 2 1 2
Fixed maturity securities | Foreign currency forwards      
Derivative Instruments, Gain (Loss) [Line Items]      
Total gains (losses) recognized for derivatives (7) (14) (50)
Gains (losses) on derivatives excluded from effectiveness testing [1] 0 (8) (64)
Gain (losses) on derivatives included in effectiveness testing [2] (7) (6) 14
Gains (losses) recognized for hedged items [2] 6 7 (12)
Net realized gains (losses) recognized for fair value hedge (1) 1 2
Fixed maturity securities | Foreign currency options      
Derivative Instruments, Gain (Loss) [Line Items]      
Total gains (losses) recognized for derivatives (26) (9) (7)
Gains (losses) on derivatives excluded from effectiveness testing [1] (25) (8) (7)
Gain (losses) on derivatives included in effectiveness testing [2] (1) (1) 0
Gains (losses) recognized for hedged items [2] 4 1 0
Net realized gains (losses) recognized for fair value hedge $ 3 $ 0 0
Fixed maturity securities | Interest rate swaptions      
Derivative Instruments, Gain (Loss) [Line Items]      
Total gains (losses) recognized for derivatives     (9)
Gains (losses) on derivatives excluded from effectiveness testing [1]     (9)
Gain (losses) on derivatives included in effectiveness testing [2]     0
Gains (losses) recognized for hedged items [2]     0
Net realized gains (losses) recognized for fair value hedge     $ 0
[1] Gains (losses) excluded from effectiveness testing includes the forward point on foreign currency forwards and time value change on foreign currency options which are reported in the consolidated statement of earnings as net investment gains (losses). It also includes the change in the fair value of the interest rate swaptions related to the time value of the swaptions which is recognized as a component of other comprehensive income (loss).
[2] Gains and losses on foreign currency forwards and options and related hedged items are reported in the consolidated statement of earnings as net investment gains (losses). For interest rate swaptions and related hedged items, gains and losses included in the hedge assessment, premium amortization and time value amortization while the hedge items are still outstanding are reported within net investment income. The time value gains and losses for interest rate swaptions when the related hedged items are redeemed are reported in net investment gains and losses consistent with the impact of the hedged item. For the years ended December 31, 2021 and 2020, gains and losses included in the hedge assessment on interest rate swaptions and related hedged items were immaterial.
v3.22.0.1
DERIVATIVE INSTRUMENTS - Schedule of Interest Rate Fair Value Hedges Hedged Items (Details) - Fixed maturity securities - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosures [Line Items]    
Carrying Amount of Hedged Assets/ (Liabilities) [1] $ 3,038 $ 4,331
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of Hedged Assets/ (Liabilities) $ 205 $ 237
[1] The balance includes hedging adjustment on discontinued hedging relationships of $205 in 2021 and $237 in 2020.
v3.22.0.1
DERIVATIVE INSTRUMENTS - Derivatives and Hedging Instruments Gain (Loss) Summary (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]      
Unrealized foreign currency translation gains (losses) during period $ (889) $ 510 $ 252
Derivative and non-derivative hedging instruments, gain (loss) recognized in other comprehensive income, before tax [1] 858 (418) 47
Net investment income      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative [2] (2) (2) (3)
Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative (805) 399 (174)
Reclassification out of Accumulated Other Comprehensive Income      
Derivative Instruments, Gain (Loss) [Line Items]      
Cash flow hedge (4)    
Fair value hedge excluded component (2)    
Cash flow hedges      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in other comprehensive income on derivative [1] 3 (2) (4)
Cash flow hedges | Net investment income      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative [2] (1) (1) (2)
Cash flow hedges | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative [3] (4) 0 (1)
Cash flow hedges | Foreign currency swaps | Variable Interest Entity      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in other comprehensive income on derivative [1] 3 (2) (4)
Cash flow hedges | Foreign currency swaps | Variable Interest Entity | Net investment income      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative [2] (1) (1) (2)
Cash flow hedges | Foreign currency swaps | Variable Interest Entity | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative (4) 0 (1)
Fair value hedges      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in other comprehensive income on derivative [1] 2 1 (8)
Fair value hedges | Net investment income      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative [2] (1) (1) (1)
Fair value hedges | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative (24) (15) (69)
Fair value hedges | Foreign currency forwards | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative [3] (1) (7) (62)
Fair value hedges | Foreign currency options | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative [3] (22) (8) (7)
Fair value hedges | Interest rate swaptions      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in other comprehensive income on derivative [1],[3] 2 1 (8)
Fair value hedges | Interest rate swaptions | Net investment income      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative [2],[3] (1) (1) (1)
Fair value hedges | Interest rate swaptions | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative [3] (1) 0 0
Net investment hedge      
Derivative Instruments, Gain (Loss) [Line Items]      
Unrealized foreign currency translation gains (losses) during period [1] 853 (417) 59
Net investment hedge | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative 25 144 6
Net investment hedge | Foreign currency forwards      
Derivative Instruments, Gain (Loss) [Line Items]      
Unrealized foreign currency translation gains (losses) during period [1] 525 (282) 83
Net investment hedge | Foreign currency forwards | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative 29 149 10
Net investment hedge | Foreign currency options      
Derivative Instruments, Gain (Loss) [Line Items]      
Unrealized foreign currency translation gains (losses) during period [1] 0 0 0
Net investment hedge | Foreign currency options | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative (4) (5) (4)
Net investment hedge | Non-derivative hedging Instruments      
Derivative Instruments, Gain (Loss) [Line Items]      
Unrealized foreign currency translation gains (losses) during period [1] 328 (135) (24)
Net investment hedge | Non-derivative hedging Instruments | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative 0 0 0
Non-qualifying strategies | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative (802) 270 (110)
Non-qualifying strategies | Foreign currency swaps | Variable Interest Entity | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative (188) (122) (68)
Non-qualifying strategies | Foreign currency swaps | Consolidated Entity Excluding Variable Interest Entities (VIE) | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative 135 29 90
Non-qualifying strategies | Foreign currency forwards | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative (707) 311 (148)
Non-qualifying strategies | Foreign currency options | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative (3) (3) 0
Non-qualifying strategies | Interest rate swaps | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative (38) 49 17
Non-qualifying strategies | Forward bond purchase commitment | Variable Interest Entity | Net investment gains (losses)      
Derivative Instruments, Gain (Loss) [Line Items]      
Gains (losses) recognized in income on derivative $ (1) $ 6 $ 0
[1] Gains and losses on cash flow hedges and the change in the fair value of interest rate swaptions related to the time value of the swaptions in fair value hedges are recorded as unrealized gains (losses). Gains and losses on net investment hedges related to changes in foreign currency spot rates are recorded in the unrealized foreign currency translation gains (losses) line in the consolidated statement of comprehensive income (loss).
[2] Interest expense/income on cash flow hedges are recorded in net investment income. For interest rate swaptions classified as fair value hedges, the change in the time value of the swaptions is recognized in other comprehensive income (loss) and amortized into net investment income over its legal term. If the swaption is early terminated but the hedge item is still outstanding, the amortization of disposal amount of the swaptions is recorded in net investment income over the remaining life of the hedged items.
[3] Impact of cash flow hedges reported as net investment gains (losses) includes $4 of losses reclassified from accumulated other comprehensive income (loss) into earnings during the year ended December 31, 2021, and an immaterial amount during the years ended December 31, 2020 and 2019, respectively. In addition, $2 of losses were reclassified from accumulated other comprehensive income (loss) into earnings during the year ended December 31, 2021, and an immaterial amount during the years ended December 31, 2020 and 2019, respectively, related to fair value hedges excluded component. Impact shown net of effect of hedged items (see Fair Value Hedges section of this Note 4 for further detail).
v3.22.0.1
DERIVATIVE INSTRUMENTS - Offsetting of Financial Assets and Derivative Assets (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Offsetting Assets [Line Items]    
Gross amount of recognized derivative assets $ 858 $ 450
Gross amount of liabilities offset in balance sheet 0 0
Net amount of derivative assets presented in balance sheet 858 450
Financial instruments, amounts not offset (471) (295)
Derivative, collateral, obligation to return securities (53) (73)
Derivative, collateral, obligation to return cash (334) (76)
Derivative asset, fair value, amount offset against collateral, subject to master netting agreement 0 6
Derivative asset, not subject to master netting arrangement 78 133
Derivative asset, fair value, amount offset against collateral, not subject to master netting agreement 78 133
Derivative asset, fair value, gross asset including not subject to master netting arrangement 936 583
Net amounts of derivative assets presented in balance sheet 936 583
Derivative asset, fair value, amount offset against collateral 78 139
Gross amounts of recognized financial instruments 3,060 1,523
Gross amounts offest in balance sheet 0 0
Net amounts of assets presented in balance sheet 3,060 1,523
Carrying value of financial instruments not offset in balance sheet (471) (295)
Securities collateral, not offset in balance sheet (53) (73)
Cash collateral, not offset in balance sheet (2,458) (1,016)
Financial instruments, amount of assets offset against collateral 78 139
Over the Counter - Bilateral    
Offsetting Assets [Line Items]    
Gross amount of recognized derivative assets 858 450
Gross amount of liabilities offset in balance sheet 0 0
Net amount of derivative assets presented in balance sheet 858 450
Financial instruments, amounts not offset (471) (295)
Derivative, collateral, obligation to return securities (53) (73)
Derivative, collateral, obligation to return cash (334) (76)
Derivative asset, fair value, amount offset against collateral, subject to master netting agreement 0 6
Derivative asset, not subject to master netting arrangement 78 133
Derivative asset, fair value, amount offset against collateral, not subject to master netting agreement 78 133
Securities Lending and Similar Arrangements    
Offsetting Assets [Line Items]    
Gross amounts of recognized financial instruments 2,124 940
Gross amounts offest in balance sheet 0 0
Net amounts of assets presented in balance sheet 2,124 940
Carrying value of financial instruments not offset in balance sheet 0 0
Securities collateral, not offset in balance sheet 0 0
Cash collateral, not offset in balance sheet (2,124) (940)
Financial instruments, amount of assets offset against collateral $ 0 $ 0
v3.22.0.1
DERIVATIVE INSTRUMENTS - Offsetting of Financial Liabilities and Derivative Liabilities (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Offsetting Liabilities [Line Items]    
Gross amount of recognized derivative liabilities $ 1,205 $ 466
Gross amount of assets offset in balance sheet 0 0
Derivative liability, fair value, amount not offset against collateral 1,205 466
Financial instruments, amounts not offset (471) (295)
Derivative, collateral, right to reclaim securities (662) (43)
Derivative, collateral, right to reclaim cash (49) (69)
Derivative liability, fair value, amount offset against collateral, subject to master netting agreement 23 59
Derivative liability, not subject to master netting arrangement 414 231
Derivative liability, fair value, amount offset against collateral, not subject to master netting agreement 414 231
Derivative liability, fair value, gross liability including not subject to master netting arrangement 1,619 697
Net amount of derivative liabilities presented in balance sheet 1,619 697
Derivative liability, fair value, amount offset against collateral 437 290
Gross amounts of recognized financial instruments, offsetting liabilities 3,781 1,661
Gross amounts offset in statement of financial position, offsetting liabilities 0 0
Net amounts of financial instruments presented in balance sheet, offsetting liabilities 3,781 1,661
Carrying value of financial instruments, liabilities not offset in balance sheet (2,595) (1,235)
Securities collateral, liabilities not offset in balance sheet (662) (43)
Cash collateral, liabilities not offset in balance sheet (49) (69)
Financial instruments, amount of liabilities offset against collateral 475 314
Over the Counter - Bilateral    
Offsetting Liabilities [Line Items]    
Gross amount of recognized derivative liabilities 1,151 466
Gross amount of assets offset in balance sheet 0 0
Derivative liability, fair value, amount not offset against collateral 1,151 466
Financial instruments, amounts not offset (471) (295)
Derivative, collateral, right to reclaim securities (662) (43)
Derivative, collateral, right to reclaim cash (14) (69)
Derivative liability, fair value, amount offset against collateral, subject to master netting agreement 4 59
Derivative liability, not subject to master netting arrangement 414 231
Derivative liability, fair value, amount offset against collateral, not subject to master netting agreement 414 231
Over the Counter - Cleared    
Offsetting Liabilities [Line Items]    
Gross amount of recognized derivative liabilities 54  
Gross amount of assets offset in balance sheet 0  
Derivative liability, fair value, amount not offset against collateral 54  
Financial instruments, amounts not offset 0  
Derivative, collateral, right to reclaim securities 0  
Derivative, collateral, right to reclaim cash (35)  
Derivative liability, fair value, amount offset against collateral, subject to master netting agreement 19  
Securities Lending and Similar Arrangements    
Offsetting Liabilities [Line Items]    
Gross amounts of recognized financial instruments, offsetting liabilities 2,162 964
Gross amounts offset in statement of financial position, offsetting liabilities 0 0
Net amounts of financial instruments presented in balance sheet, offsetting liabilities 2,162 964
Carrying value of financial instruments, liabilities not offset in balance sheet (2,124) (940)
Securities collateral, liabilities not offset in balance sheet 0 0
Cash collateral, liabilities not offset in balance sheet 0 0
Financial instruments, amount of liabilities offset against collateral $ 38 $ 24
v3.22.0.1
FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Assets:    
Available for sale, fixed maturity securities $ 98,696 $ 105,882
Equity securities 1,603 1,283
Other investments 1,726 1,139
Cash and cash equivalents 5,051 5,141
Asset derivatives 936 583
Total assets 108,012 114,028
Liabilities:    
Liability derivatives 1,619 697
Total liabilities 1,619 697
Foreign currency swaps    
Assets:    
Asset derivatives 137 180
Liabilities:    
Liability derivatives 427 312
Foreign currency forwards    
Assets:    
Asset derivatives 791 402
Liabilities:    
Liability derivatives 1,138 385
Foreign currency options    
Assets:    
Asset derivatives 8 1
Interest rate swaps    
Liabilities:    
Liability derivatives 54  
Government and agencies    
Assets:    
Available for sale, fixed maturity securities 33,820 37,350
Municipalities    
Assets:    
Available for sale, fixed maturity securities 3,036 3,018
Mortgage- and asset-backed securities    
Assets:    
Available for sale, fixed maturity securities 1,246 1,038
Public utilities    
Assets:    
Available for sale, fixed maturity securities 10,051 10,817
Sovereign and supranational    
Assets:    
Available for sale, fixed maturity securities 1,115 1,382
Banks/financial institutions    
Assets:    
Available for sale, fixed maturity securities 11,591 12,060
Other corporate    
Assets:    
Available for sale, fixed maturity securities 37,837 40,217
Level 1    
Assets:    
Available for sale, fixed maturity securities 32,532 36,032
Equity securities 1,340 1,095
Other investments 1,726 1,139
Cash and cash equivalents 5,051 5,141
Asset derivatives 0 0
Total assets 40,649 43,407
Liabilities:    
Total liabilities 0 0
Level 1 | Foreign currency swaps    
Assets:    
Asset derivatives 0 0
Liabilities:    
Liability derivatives 0 0
Level 1 | Foreign currency forwards    
Assets:    
Asset derivatives 0 0
Liabilities:    
Liability derivatives 0 0
Level 1 | Foreign currency options    
Assets:    
Asset derivatives 0 0
Level 1 | Interest rate swaps    
Liabilities:    
Liability derivatives 0  
Level 1 | Government and agencies    
Assets:    
Available for sale, fixed maturity securities 32,532 36,032
Level 1 | Municipalities    
Assets:    
Available for sale, fixed maturity securities 0 0
Level 1 | Mortgage- and asset-backed securities    
Assets:    
Available for sale, fixed maturity securities 0 0
Level 1 | Public utilities    
Assets:    
Available for sale, fixed maturity securities 0 0
Level 1 | Sovereign and supranational    
Assets:    
Available for sale, fixed maturity securities 0 0
Level 1 | Banks/financial institutions    
Assets:    
Available for sale, fixed maturity securities 0 0
Level 1 | Other corporate    
Assets:    
Available for sale, fixed maturity securities 0 0
Level 2    
Assets:    
Available for sale, fixed maturity securities 64,866 68,833
Equity securities 90 86
Other investments 0 0
Cash and cash equivalents 0 0
Asset derivatives 936 450
Total assets 65,892 69,369
Liabilities:    
Total liabilities 1,619 466
Level 2 | Foreign currency swaps    
Assets:    
Asset derivatives 137 47
Liabilities:    
Liability derivatives 427 81
Level 2 | Foreign currency forwards    
Assets:    
Asset derivatives 791 402
Liabilities:    
Liability derivatives 1,138 385
Level 2 | Foreign currency options    
Assets:    
Asset derivatives 8 1
Level 2 | Interest rate swaps    
Liabilities:    
Liability derivatives 54  
Level 2 | Government and agencies    
Assets:    
Available for sale, fixed maturity securities 1,288 1,318
Level 2 | Municipalities    
Assets:    
Available for sale, fixed maturity securities 3,036 3,018
Level 2 | Mortgage- and asset-backed securities    
Assets:    
Available for sale, fixed maturity securities 955 814
Level 2 | Public utilities    
Assets:    
Available for sale, fixed maturity securities 9,558 10,395
Level 2 | Sovereign and supranational    
Assets:    
Available for sale, fixed maturity securities 1,072 1,334
Level 2 | Banks/financial institutions    
Assets:    
Available for sale, fixed maturity securities 11,546 12,036
Level 2 | Other corporate    
Assets:    
Available for sale, fixed maturity securities 37,411 39,918
Level 3    
Assets:    
Available for sale, fixed maturity securities 1,298 1,017
Equity securities 173 102
Other investments 0 0
Cash and cash equivalents 0 0
Asset derivatives 0 133
Total assets 1,471 1,252
Liabilities:    
Total liabilities 0 231
Level 3 | Foreign currency swaps    
Assets:    
Asset derivatives 0 133
Liabilities:    
Liability derivatives 0 231
Level 3 | Foreign currency forwards    
Assets:    
Asset derivatives 0 0
Liabilities:    
Liability derivatives 0 0
Level 3 | Foreign currency options    
Assets:    
Asset derivatives 0 0
Level 3 | Interest rate swaps    
Liabilities:    
Liability derivatives 0  
Level 3 | Government and agencies    
Assets:    
Available for sale, fixed maturity securities 0 0
Level 3 | Municipalities    
Assets:    
Available for sale, fixed maturity securities 0 0
Level 3 | Mortgage- and asset-backed securities    
Assets:    
Available for sale, fixed maturity securities 291 224
Level 3 | Public utilities    
Assets:    
Available for sale, fixed maturity securities 493 422
Level 3 | Sovereign and supranational    
Assets:    
Available for sale, fixed maturity securities 43 48
Level 3 | Banks/financial institutions    
Assets:    
Available for sale, fixed maturity securities 45 24
Level 3 | Other corporate    
Assets:    
Available for sale, fixed maturity securities $ 426 $ 299
v3.22.0.1
FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets and Liabilities Carried at Cost or Amortized Cost (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Other investments $ 3,842 $ 2,429
Assets:    
Securities held to maturity, fixed maturities, amortized cost 22,008 24,474
Held to maturity, fixed maturity securities, fair value 26,869 30,399
Commercial mortgage and other loans 11,786 10,554
Commercial mortgage and other loans, fair value 11,996 10,655
Other investments, carried at amortized cost 22 [1] 26 [2]
Other investments, carried at amortized cost, fair value 22 [1] 26 [2]
Total financial instruments, assets, not carried at fair value 33,808 35,044
Assets, fair value disclosure, financial instruments, carried at cost 38,887 41,080
Liabilities:    
Other policyholders' funds 7,072 7,824
Other policyholders' funds fair value disclosure 6,957 7,709
Notes payable 7,839 7,745
Notes payable, fair value disclosure 8,539 8,684
Total financial instrument liabilities not carried at fair value 14,911 15,569
Liabilities fair value disclosure financial instruments carried at cost 15,496 16,393
Government and agencies    
Assets:    
Securities held to maturity, fixed maturities, amortized cost 21,086 23,445
Held to maturity, fixed maturity securities, fair value 25,699 29,070
Municipalities    
Assets:    
Securities held to maturity, fixed maturities, amortized cost 335 377
Held to maturity, fixed maturity securities, fair value 436 499
Public utilities    
Assets:    
Securities held to maturity, fixed maturities, amortized cost 43 47
Held to maturity, fixed maturity securities, fair value 55 61
Sovereign and supranational    
Assets:    
Securities held to maturity, fixed maturities, amortized cost 514 571
Held to maturity, fixed maturity securities, fair value 650 736
Other corporate    
Assets:    
Securities held to maturity, fixed maturities, amortized cost 22 24
Held to maturity, fixed maturity securities, fair value 29 33
Policy loans    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Other investments 236 260
Equity method investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Other investments 1,858 1,004
Level 1    
Assets:    
Held to maturity, fixed maturity securities, fair value 25,469 28,810
Commercial mortgage and other loans, fair value 0 0
Other investments, carried at amortized cost, fair value 0 [1] 0 [2]
Assets, fair value disclosure, financial instruments, carried at cost 25,469 28,810
Liabilities:    
Other policyholders' funds fair value disclosure 0 0
Notes payable, fair value disclosure 0 0
Liabilities fair value disclosure financial instruments carried at cost 0 0
Level 1 | Government and agencies    
Assets:    
Held to maturity, fixed maturity securities, fair value 25,469 28,810
Level 1 | Municipalities    
Assets:    
Held to maturity, fixed maturity securities, fair value 0 0
Level 1 | Public utilities    
Assets:    
Held to maturity, fixed maturity securities, fair value 0 0
Level 1 | Sovereign and supranational    
Assets:    
Held to maturity, fixed maturity securities, fair value 0 0
Level 1 | Other corporate    
Assets:    
Held to maturity, fixed maturity securities, fair value 0 0
Level 2    
Assets:    
Held to maturity, fixed maturity securities, fair value 1,400 1,589
Commercial mortgage and other loans, fair value 0 0
Other investments, carried at amortized cost, fair value 22 [1] 26 [2]
Assets, fair value disclosure, financial instruments, carried at cost 1,422 1,615
Liabilities:    
Other policyholders' funds fair value disclosure 0 0
Notes payable, fair value disclosure 8,280 8,396
Liabilities fair value disclosure financial instruments carried at cost 8,280 8,396
Level 2 | Government and agencies    
Assets:    
Held to maturity, fixed maturity securities, fair value 230 260
Level 2 | Municipalities    
Assets:    
Held to maturity, fixed maturity securities, fair value 436 499
Level 2 | Public utilities    
Assets:    
Held to maturity, fixed maturity securities, fair value 55 61
Level 2 | Sovereign and supranational    
Assets:    
Held to maturity, fixed maturity securities, fair value 650 736
Level 2 | Other corporate    
Assets:    
Held to maturity, fixed maturity securities, fair value 29 33
Level 3    
Assets:    
Held to maturity, fixed maturity securities, fair value 0 0
Commercial mortgage and other loans, fair value 11,996 10,655
Other investments, carried at amortized cost, fair value 0 [1] 0 [2]
Assets, fair value disclosure, financial instruments, carried at cost 11,996 10,655
Liabilities:    
Other policyholders' funds fair value disclosure 6,957 7,709
Notes payable, fair value disclosure 259 288
Liabilities fair value disclosure financial instruments carried at cost 7,216 7,997
Level 3 | Government and agencies    
Assets:    
Held to maturity, fixed maturity securities, fair value 0 0
Level 3 | Municipalities    
Assets:    
Held to maturity, fixed maturity securities, fair value 0 0
Level 3 | Public utilities    
Assets:    
Held to maturity, fixed maturity securities, fair value 0 0
Level 3 | Sovereign and supranational    
Assets:    
Held to maturity, fixed maturity securities, fair value 0 0
Level 3 | Other corporate    
Assets:    
Held to maturity, fixed maturity securities, fair value $ 0 $ 0
[1] Excludes policy loans of $236 and equity method investments of $1,858, at carrying value
[2] Excludes policy loans of $260 and equity method investments of $1,004, at carrying value
v3.22.0.1
FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets by Pricing Source, Securities Carried at Fair Value (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities $ 98,696 $ 105,882
Equity securities 1,603 1,283
Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 32,532 36,032
Equity securities 1,340 1,095
Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 64,866 68,833
Equity securities 90 86
Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 1,298 1,017
Equity securities 173 102
Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Equity securities 1,430 1,181
Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Equity securities 1,340 1,095
Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Equity securities 90 86
Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Equity securities 0 0
Net asset value valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Equity securities 173 102
Net asset value valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Equity securities 0 0
Net asset value valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Equity securities 0 0
Net asset value valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Equity securities 173 102
Government and agencies    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 33,820 37,350
Government and agencies | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 32,532 36,032
Government and agencies | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 1,288 1,318
Government and agencies | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Government and agencies | Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 33,340 37,350
Government and agencies | Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 32,532 36,032
Government and agencies | Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 808 1,318
Government and agencies | Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Government and agencies | Internal valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 480  
Government and agencies | Internal valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Government and agencies | Internal valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 480  
Government and agencies | Internal valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Municipalities    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 3,036 3,018
Municipalities | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Municipalities | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 3,036 3,018
Municipalities | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Municipalities | Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 2,222 3,018
Municipalities | Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Municipalities | Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 2,222 3,018
Municipalities | Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Municipalities | Internal valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 814  
Municipalities | Internal valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Municipalities | Internal valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 814  
Municipalities | Internal valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Mortgage- and asset-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 1,246 1,038
Mortgage- and asset-backed securities | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Mortgage- and asset-backed securities | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 955 814
Mortgage- and asset-backed securities | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 291 224
Mortgage- and asset-backed securities | Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 955 364
Mortgage- and asset-backed securities | Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Mortgage- and asset-backed securities | Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 955 364
Mortgage- and asset-backed securities | Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Mortgage- and asset-backed securities | Consensus pricing valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 291 674
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 450
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 291 224
Public utilities    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 10,051 10,817
Public utilities | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Public utilities | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 9,558 10,395
Public utilities | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 493 422
Public utilities | Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 4,527 10,395
Public utilities | Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Public utilities | Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 4,527 10,395
Public utilities | Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Public utilities | Discounted cash flow technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 493 422
Public utilities | Discounted cash flow technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Public utilities | Discounted cash flow technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Public utilities | Discounted cash flow technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 493 422
Public utilities | Internal valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 5,031  
Public utilities | Internal valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Public utilities | Internal valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 5,031  
Public utilities | Internal valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Sovereign and supranational    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 1,115 1,382
Sovereign and supranational | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Sovereign and supranational | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 1,072 1,334
Sovereign and supranational | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 43 48
Sovereign and supranational | Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 273 1,334
Sovereign and supranational | Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Sovereign and supranational | Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 273 1,334
Sovereign and supranational | Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Sovereign and supranational | Consensus pricing valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities   48
Sovereign and supranational | Consensus pricing valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities   0
Sovereign and supranational | Consensus pricing valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities   0
Sovereign and supranational | Consensus pricing valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities   48
Sovereign and supranational | Discounted cash flow technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 43  
Sovereign and supranational | Discounted cash flow technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Sovereign and supranational | Discounted cash flow technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Sovereign and supranational | Discounted cash flow technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 43 48
Sovereign and supranational | Internal valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 799  
Sovereign and supranational | Internal valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Sovereign and supranational | Internal valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 799  
Sovereign and supranational | Internal valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Banks/financial institutions    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 11,591 12,060
Banks/financial institutions | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Banks/financial institutions | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 11,546 12,036
Banks/financial institutions | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 45 24
Banks/financial institutions | Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 5,237 12,036
Banks/financial institutions | Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Banks/financial institutions | Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 5,237 12,036
Banks/financial institutions | Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Banks/financial institutions | Consensus pricing valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 45 24
Banks/financial institutions | Consensus pricing valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Banks/financial institutions | Consensus pricing valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Banks/financial institutions | Consensus pricing valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 45 24
Banks/financial institutions | Internal valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 6,309  
Banks/financial institutions | Internal valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Banks/financial institutions | Internal valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 6,309  
Banks/financial institutions | Internal valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Other corporate    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 37,837 40,217
Other corporate | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Other corporate | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 37,411 39,918
Other corporate | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 426 299
Other corporate | Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 29,495 39,886
Other corporate | Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Other corporate | Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 29,495 39,886
Other corporate | Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Other corporate | Discounted cash flow technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 426 331
Other corporate | Discounted cash flow technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 0
Other corporate | Discounted cash flow technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0 32
Other corporate | Discounted cash flow technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 426 $ 299
Other corporate | Internal valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 7,916  
Other corporate | Internal valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 0  
Other corporate | Internal valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities 7,916  
Other corporate | Internal valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]    
Available for sale, fixed maturity securities $ 0  
v3.22.0.1
FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets by Pricing Source, Securities Carried at Amortized Cost (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value $ 26,869 $ 30,399
Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 25,469 28,810
Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 1,400 1,589
Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Government and agencies    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 25,699 29,070
Government and agencies | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 25,469 28,810
Government and agencies | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 230 260
Government and agencies | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Government and agencies | Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 25,699 29,070
Government and agencies | Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 25,469 28,810
Government and agencies | Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 230 260
Government and agencies | Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Municipalities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 436 499
Municipalities | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Municipalities | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 436 499
Municipalities | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Municipalities | Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 436 499
Municipalities | Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Municipalities | Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 436 499
Municipalities | Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Public utilities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 55 61
Public utilities | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Public utilities | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 55 61
Public utilities | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Public utilities | Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 55 61
Public utilities | Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Public utilities | Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 55 61
Public utilities | Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Sovereign and supranational    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 650 736
Sovereign and supranational | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Sovereign and supranational | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 650 736
Sovereign and supranational | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Sovereign and supranational | Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 313 736
Sovereign and supranational | Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Sovereign and supranational | Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 313 736
Sovereign and supranational | Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Sovereign and supranational | Consensus pricing valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 337  
Sovereign and supranational | Consensus pricing valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0  
Sovereign and supranational | Consensus pricing valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 337  
Sovereign and supranational | Consensus pricing valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0  
Other corporate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 29 33
Other corporate | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Other corporate | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 29 33
Other corporate | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Other corporate | Third party pricing vendor valuation technique    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 29 33
Other corporate | Third party pricing vendor valuation technique | Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 0 0
Other corporate | Third party pricing vendor valuation technique | Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value 29 33
Other corporate | Third party pricing vendor valuation technique | Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Held to maturity, fixed maturity securities, fair value $ 0 $ 0
v3.22.0.1
FAIR VALUE MEASUREMENTS - Changes in Investments and Derivatives Carried at Fair Value Classified as Level 3 (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period $ 1,021 $ 810
Net investment gains (losses) included in earnings (135) (124)
Unrealized gains (losses) included in other comprehensive income (loss) (65) 38
Purchases 490 306
Issuances 17 0
Sales (33) (6)
Settlements (38) (12)
Transfers into Level 3 107 26
Transfers out of Level 3   (17)
Transfers out of level 3 107  
Balance, end of period 1,471 1,021
Change in unrealized gains (losses) still held (217) (139)
Foreign currency swaps    
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]    
Balance, beginning of period (98) 43
Net investment gains (losses) included in earnings (158) (139)
Unrealized gains (losses) included in other comprehensive income (loss) (1) (2)
Purchases 0 0
Issuances 0 0
Sales 0 0
Settlements 0 0
Transfers into Level 3 0 0
Transfers out of Level 3 257 0
Balance, end of period 0 (98)
Change in unrealized gains (losses) still held (158) (139)
Fixed maturity securities | Mortgage- and asset-backed securities    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 224 178
Net investment gains (losses) included in earnings 0 0
Unrealized gains (losses) included in other comprehensive income (loss) (25) 9
Purchases 169 30
Issuances 0 0
Sales 0 0
Settlements 0 (2)
Transfers into Level 3 0 9
Transfers out of Level 3 (77) 0
Balance, end of period 291 224
Change in unrealized gains (losses) still held (24) 0
Fixed maturity securities | Public utilities    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 422 224
Net investment gains (losses) included in earnings 0 (1)
Unrealized gains (losses) included in other comprehensive income (loss) (21) 19
Purchases 167 174
Issuances 0 0
Sales (2) 0
Settlements (21) (9)
Transfers into Level 3 0 15
Transfers out of Level 3 (52) 0
Balance, end of period 493 422
Change in unrealized gains (losses) still held (23) 0
Fixed maturity securities | Sovereign and supranational    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 48 0
Net investment gains (losses) included in earnings 0 0
Unrealized gains (losses) included in other comprehensive income (loss) (5) 0
Purchases 0 48
Issuances 0 0
Sales (23) 0
Settlements 0 0
Transfers into Level 3 23 0
Transfers out of Level 3 0 0
Balance, end of period 43 48
Change in unrealized gains (losses) still held (4) 0
Fixed maturity securities | Banks/financial institutions    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 24 23
Net investment gains (losses) included in earnings 0 0
Unrealized gains (losses) included in other comprehensive income (loss) (2) 0
Purchases 23 1
Issuances 0 0
Sales 0 0
Settlements 0 0
Transfers into Level 3 0 0
Transfers out of Level 3 0 0
Balance, end of period 45 24
Change in unrealized gains (losses) still held (2) 0
Fixed maturity securities | Other corporate    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 299 262
Net investment gains (losses) included in earnings 2 0
Unrealized gains (losses) included in other comprehensive income (loss) (11) 12
Purchases 90 39
Issuances 0 0
Sales 0 0
Settlements (17) (1)
Transfers into Level 3 84 2
Transfers out of Level 3 (21) (15)
Balance, end of period 426 299
Change in unrealized gains (losses) still held (27) 0
Equity securities    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 102 80
Net investment gains (losses) included in earnings 21 16
Unrealized gains (losses) included in other comprehensive income (loss) 0 0
Purchases 41 14
Issuances 17 0
Sales (8) (6)
Settlements 0 0
Transfers into Level 3 0 0
Transfers out of Level 3 0 (2)
Balance, end of period 173 102
Change in unrealized gains (losses) still held $ 21 $ 0
v3.22.0.1
FAIR VALUE MEASUREMENTS - Fair Value Measurement Inputs and Valuation Techniques (Details)
$ in Millions
Dec. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities $ 98,696 $ 105,882
Equity securities 1,603 1,283
Asset derivatives 936 583
Liability derivatives 1,619 697
Assets, fair value 108,012 114,028
Liabilities, fair value 1,619 697
Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 1,298 1,017
Equity securities 173 102
Asset derivatives 0 133
Assets, fair value 1,471 1,252
Liabilities, fair value 0 231
Net asset value valuation technique    
Fair Value Measurement Inputs and Valuation Technique    
Equity securities 173 102
Net asset value valuation technique | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Equity securities 173 102
Foreign currency swaps    
Fair Value Measurement Inputs and Valuation Technique    
Asset derivatives 137 180
Liability derivatives 427 312
Foreign currency swaps | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Asset derivatives 0 133
Liability derivatives 0 231
Foreign currency swaps | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Discounted cash flow technique | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Asset derivatives   69
Liability derivatives   160
Foreign currency swaps | Fair Value, Unobservable Input, Interest Rates (USD) and Interest Rates (JPY) | Discounted cash flow technique | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Asset derivatives   64
Liability derivatives   $ 71
Foreign currency swaps | Credit Spread | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Lower Limit | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Derivative asset, measurement input   0.0022
Derivative liability, measurement input   0.0041
Foreign currency swaps | Credit Spread | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Upper Limit | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Derivative asset, measurement input   0.0128
Derivative liability, measurement input   0.0140
Dollar-denominated    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 40,709 $ 41,611
Equity securities 817 $ 603
Dollar-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Lower Limit | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Derivative asset, measurement input [1]   0.0093
Derivative liability, measurement input [1]   0.0093
Dollar-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Upper Limit | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Derivative asset, measurement input [1]   0.0140
Derivative liability, measurement input [1]   0.0112
Dollar-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD) and Interest Rates (JPY) | Lower Limit | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Derivative asset, measurement input [1]   0.0093
Derivative liability, measurement input [1]   0.0093
Dollar-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD) and Interest Rates (JPY) | Upper Limit | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Derivative asset, measurement input [1]   0.0140
Derivative liability, measurement input [1]   0.0112
Yen-denominated    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 57,987 $ 64,271
Equity securities 744 $ 680
Yen-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Lower Limit | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Derivative asset, measurement input [2]   0.0005
Derivative liability, measurement input [2]   0.0005
Yen-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD), Interest Rates (JPY), and CDS Spreads | Upper Limit | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Derivative asset, measurement input [2]   0.0043
Derivative liability, measurement input [2]   0.0035
Yen-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD) and Interest Rates (JPY) | Lower Limit | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Derivative asset, measurement input [2]   0.0005
Derivative liability, measurement input [2]   0.0005
Yen-denominated | Foreign currency swaps | Discount Rate | Fair Value, Unobservable Input, Interest Rates (USD) and Interest Rates (JPY) | Upper Limit | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Derivative asset, measurement input [2]   0.0043
Derivative liability, measurement input [2]   0.0035
Mortgage- and asset-backed securities    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 1,246 $ 1,038
Mortgage- and asset-backed securities | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 291 224
Mortgage- and asset-backed securities | Consensus pricing valuation technique    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 291 674
Mortgage- and asset-backed securities | Consensus pricing valuation technique | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 291 224
Mortgage- and asset-backed securities | Dollar-denominated    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 928 670
Mortgage- and asset-backed securities | Yen-denominated    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 318 368
Banks/financial institutions    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 11,591 12,060
Banks/financial institutions | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 45 24
Banks/financial institutions | Consensus pricing valuation technique    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 45 24
Banks/financial institutions | Consensus pricing valuation technique | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 45 24
Banks/financial institutions | Dollar-denominated    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 3,913 3,724
Banks/financial institutions | Yen-denominated    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 7,678 8,336
Public utilities    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 10,051 10,817
Public utilities | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 493 422
Public utilities | Discounted cash flow technique    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 493 422
Public utilities | Discounted cash flow technique | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 493 422
Public utilities | Dollar-denominated    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 4,685 4,945
Public utilities | Yen-denominated    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 5,366 5,872
Other corporate    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 37,837 40,217
Other corporate | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 426 299
Other corporate | Discounted cash flow technique    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 426 331
Other corporate | Discounted cash flow technique | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 426 299
Other corporate | Dollar-denominated    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 29,180 30,393
Other corporate | Yen-denominated    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 8,657 9,824
Sovereign and supranational    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 1,115 1,382
Sovereign and supranational | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 43 48
Sovereign and supranational | Consensus pricing valuation technique    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities   48
Sovereign and supranational | Consensus pricing valuation technique | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities   48
Sovereign and supranational | Discounted cash flow technique    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 43  
Sovereign and supranational | Discounted cash flow technique | Level 3    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 43 48
Sovereign and supranational | Dollar-denominated    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities 273 293
Sovereign and supranational | Yen-denominated    
Fair Value Measurement Inputs and Valuation Technique    
Available for sale, fixed maturity securities $ 842 $ 1,089
[1] Inputs derived from U.S. long-term rates to accommodate long maturity nature of the Company's swaps
[2] Inputs derived from Japan long-term rates to accommodate long maturity nature of the Company's swaps
v3.22.0.1
DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES - Additional Information (Detail) - USD ($)
$ in Billions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Deferred Policy Acquisition Costs Disclosures [Abstract]      
Capitalization of deferred policy acquisition costs $ 1.1 $ 1.2 $ 1.5
Commissions deferred as a percentage of total acquisition costs 71.00% 77.00% 74.00%
Personnel, compensation and benefit expenses as a percentage of insurance expenses 57.00% 59.00% 57.00%
v3.22.0.1
DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES - Rollforward of Deferred Policy Acquisition Costs by Segment (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Deferred policy acquisition costs:      
Balance, beginning of year $ 10,441    
Capitalization 1,100 $ 1,200 $ 1,500
Amortization (1,170) (1,214) (1,282)
Balance, end of year 9,525 10,441  
Aflac Japan      
Deferred policy acquisition costs:      
Balance, beginning of year 6,991 6,584  
Capitalization 593 665  
Amortization (653) (644) (709)
Foreign currency translation and other (698) 386  
Balance, end of year 6,233 6,991 6,584
Aflac U.S.      
Deferred policy acquisition costs:      
Balance, beginning of year 3,450 3,544  
Capitalization 470 486  
Amortization (517) (570) (573)
Foreign currency translation and other (111) (10)  
Balance, end of year $ 3,292 $ 3,450 $ 3,544
v3.22.0.1
DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES - Advertising Expense (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Advertising Costs [Line Items]      
Advertising expense $ 229 $ 184 $ 219
Aflac Japan      
Advertising Costs [Line Items]      
Advertising expense 91 72 101
Aflac U.S.      
Advertising Costs [Line Items]      
Advertising expense $ 138 $ 112 $ 118
v3.22.0.1
DEFERRED POLICY ACQUISITION COSTS AND INSURANCE EXPENSES - Depreciation and Other Amortization Expense (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Deferred Policy Acquisition Costs Disclosures [Abstract]      
Depreciation expense $ 39 $ 36 $ 40
Other amortization expense 6 5 1
Total depreciation and other amortization expense $ 45 $ 41 $ 41
v3.22.0.1
POLICY LIABILITIES - Additional Information (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Percentage of future policy benefits out of policy liabilities 86.00%    
Percentage of unpaid policy claims out of policy liabilities 5.00%    
Percentage of unearned premiums out of policy liabilities 2.00%    
Percentage of other poliyholders' funds out of policy liabilities 7.00%    
Percentage of advanced premiums to unearned premiums 54.00% 60.00%  
Percentage of annuities to other policyholders' fund 97.00% 97.00%  
Aflac Japan      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability for future policy benefits, interest rate 3.10% 3.10% 3.20%
Aflac U.S.      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability for future policy benefits, interest rate 5.10% 5.20% 5.30%
Health insurance      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Prior year claims and claims adjustment expense $ (860) $ (540) $ (552)
Health insurance | Aflac Japan      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Prior year claims and claims adjustment expense $ (460)    
Percentage of total prior year claims and claims adjustment expense 54.00%    
Liability for unpaid claims and claims adjustment expense, foreign currency translation gain (loss) $ (35)    
Prior year claims and claims adjustment expense excluding effect of foreign currency $ (495)    
Percentage of total prior year claims and claims adjustment expense excluding effect of foreign currency 58.00%    
Health insurance | Aflac U.S.      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Prior year claims and claims adjustment expense $ (400)    
Percentage of total prior year claims and claims adjustment expense 46.00%    
v3.22.0.1
POLICY LIABILITIES - Liability for Future Policy Benefits (Detail) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability amounts $ 90,588 $ 97,783  
Intercompany eliminations      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability amounts [1] $ (456) $ (545)  
Liability for future policy benefits, interest rate 2.00%    
Aflac Japan      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability for future policy benefits, interest rate 3.10% 3.10% 3.20%
Aflac U.S.      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability for future policy benefits, interest rate 5.10% 5.20% 5.30%
Health insurance | Aflac Japan      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability amounts $ 49,421 $ 54,659  
Health insurance | Aflac Japan | Lower Limit      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability for future policy benefits, interest rate 0.60%    
Health insurance | Aflac Japan | Upper Limit      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability for future policy benefits, interest rate 6.75%    
Health insurance | Aflac U.S.      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability amounts $ 8,949 8,834  
Health insurance | Aflac U.S. | Lower Limit      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability for future policy benefits, interest rate 3.00%    
Health insurance | Aflac U.S. | Upper Limit      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability for future policy benefits, interest rate 8.00%    
Life insurance | Aflac Japan      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability amounts $ 31,756 33,993  
Life insurance | Aflac Japan | Lower Limit      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability for future policy benefits, interest rate 0.60%    
Life insurance | Aflac Japan | Upper Limit      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability for future policy benefits, interest rate 4.50%    
Life insurance | Aflac U.S.      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability amounts $ 918 $ 842  
Life insurance | Aflac U.S. | Lower Limit      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability for future policy benefits, interest rate 2.50%    
Life insurance | Aflac U.S. | Upper Limit      
Liability for Future Policy Benefit, by Product Segment [Line Items]      
Liability for future policy benefits, interest rate 6.00%    
[1] Elimination entry necessary due to recapture of a portion of policy liabilities ceded externally, as a result of the reinsurance retrocession transaction as described in Note 8 of the Notes to the Consolidated Financial Statements
v3.22.0.1
POLICY LIABILITIES - Changes in Liability for Unpaid Policy Claims (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Liability for Unpaid Claims and Claims Expenses      
Unpaid supplemental health claims, beginning of year $ 5,187 $ 4,659  
Net balance, beginning of year 5,187    
Less claims paid during the year on claims incurred during:      
Net balance, end of year 4,836 5,187  
Total liability for unpaid policy claims 4,836 5,187 $ 4,659
Zurich North America's U.S. Corporate Life and Pensions business      
Less claims paid during the year on claims incurred during:      
Liability for Unpaid Claims and Claims Adjustment Expense, Business Acquisitions 0 99 0
Health insurance      
Liability for Unpaid Claims and Claims Expenses      
Unpaid supplemental health claims, beginning of year 4,389 3,968 3,952
Less reinsurance recoverables 39 30 27
Net balance, beginning of year 4,350 3,938 3,925
Add claims incurred during the year related to:      
Current year 6,969 7,179 7,216
Prior years (860) (540) (552)
Total incurred 6,109 6,639 6,664
Less claims paid during the year on claims incurred during:      
Current year 4,356 4,488 4,715
Prior years 1,827 1,966 1,965
Total paid 6,183 6,454 6,680
Effect of foreign exchange rate changes on unpaid claims (246) 128 29
Net balance, end of year 4,030 4,350 3,938
Add reinsurance recoverables 37 39 30
Total liability for unpaid policy claims 4,067 4,389 3,968
Life insurance      
Liability for Unpaid Claims and Claims Expenses      
Unpaid supplemental health claims, beginning of year 798 691  
Less claims paid during the year on claims incurred during:      
Total liability for unpaid policy claims $ 769 $ 798 $ 691
v3.22.0.1
REINSURANCE Additional Information (Detail)
$ in Millions, ¥ in Billions
 12 Months Ended
Dec. 31, 2021
JPY (¥)
Dec. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
Effects of Reinsurance [Line Items]      
Percent change in spot yen/dollar exchange rate   (10.00%)  
Percent change in ceded reserves   9.60%  
Aflac Japan      
Effects of Reinsurance [Line Items]      
Committed reinsurance facility | ¥ ¥ 120    
Aflac Japan | Closed block      
Effects of Reinsurance [Line Items]      
Reinsurance deferred profit liability   $ 859  
Reinsurance recoverable   $ 937 $ 1,000
v3.22.0.1
REINSURANCE Effect of Reinsurance on Premiums and Benefits and Claims (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Effects of Reinsurance [Line Items]      
Direct premium income $ 17,857 $ 18,955 $ 19,122
Ceded premiums (504) (553) (547)
Assumed premiums earned 294 220 205
Net premium income 17,647 18,622 18,780
Direct benefits and claims 10,716 12,080 12,237
Benefits and claims, net 10,576 11,796 11,942
Intercompany eliminations      
Effects of Reinsurance [Line Items]      
Ceded benefits and claims 31 39 41
Assumed benefits and claims from other companies (31) (39) (41)
All other      
Effects of Reinsurance [Line Items]      
Ceded premiums (73) (87) (69)
Assumed premiums earned 114 25 5
Ceded benefits and claims (36) (63) (57)
Assumed benefits and claims from other companies 110 18 1
Aflac Japan      
Effects of Reinsurance [Line Items]      
Net premium income 11,853 12,670 12,772
Benefits and claims, net 7,963 8,851 8,877
Aflac Japan | Closed block      
Effects of Reinsurance [Line Items]      
Ceded premiums (431) (466) (478)
Assumed premiums earned 180 195 200
Ceded benefits and claims (379) (419) (433)
Assumed benefits and claims from other companies $ 165 $ 180 $ 194
v3.22.0.1
NOTES PAYABLE AND LEASE OBLIGATIONS - Additional Information (Detail)
¥ in Millions, $ in Millions
 1 Months Ended 12 Months Ended
Apr. 12, 2019
JPY (¥)
May 31, 2021
USD ($)
Mar. 31, 2021
USD ($)
series
Apr. 30, 2020
USD ($)
Sep. 30, 2019
Oct. 31, 2018
USD ($)
series
Oct. 31, 2017
JPY (¥)
Dec. 31, 2016
USD ($)
Nov. 30, 2014
USD ($)
Jun. 30, 2013
USD ($)
Dec. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
series
Dec. 31, 2019
USD ($)
Dec. 31, 2021
JPY (¥)
Apr. 30, 2021
JPY (¥)
series
Mar. 31, 2021
JPY (¥)
series
Dec. 31, 2020
JPY (¥)
series
Sep. 30, 2020
JPY (¥)
Oct. 31, 2018
JPY (¥)
series
Dec. 31, 2017
Sep. 30, 2017
USD ($)
series
Jan. 31, 2017
JPY (¥)
Mar. 31, 2016
USD ($)
Mar. 31, 2016
JPY (¥)
Nov. 30, 2014
JPY (¥)
Jun. 30, 2013
JPY (¥)
Aug. 31, 2010
USD ($)
Dec. 31, 2009
USD ($)
Debt Instrument [Line Items]                                                        
Number of series of senior notes issued through a U.S. public debt offering (in series) | series     4     3           4     5 4 4   3   2              
Operating lease, cost | $                     $ 58 $ 56 $ 54                              
Operating lease, payments | $                     $ 56 $ 54 $ 52                              
Operating lease, liability                     Notes payable and lease obligations Notes payable and lease obligations   Notes payable and lease obligations     Notes payable and lease obligations                      
Finance lease, liability                     Notes payable and lease obligations Notes payable and lease obligations   Notes payable and lease obligations     Notes payable and lease obligations                      
3.60% senior notes due April 2030                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate       3.60%             3.60% 3.60%   3.60%     3.60%                      
Debt instrument, redemption, description       These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 45 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.                                                
Debt instrument, principal amount | $       $ 1,000                                                
.300% senior notes due September 2025                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate     0.30%               0.30%     0.30%   0.30%                        
Debt instrument, principal amount                           ¥ 12,400   ¥ 12,400                        
.550% senior notes due March 2030                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate     0.55%               0.55%     0.55%   0.55%                        
Debt instrument, principal amount                           ¥ 13,300   ¥ 13,300                        
.750% senior notes due March 2032                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate     0.75%               0.75% 0.75%   0.75%   0.75% 0.75%                      
Debt instrument, principal amount                           ¥ 20,700   ¥ 20,700 ¥ 20,700                      
.830% senior notes due March 2035                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate     0.83%               0.83% 0.83%   0.83%   0.83% 0.83%                      
Debt instrument, principal amount                           ¥ 10,600   ¥ 10,600 ¥ 10,600                      
.500% senior notes due December 2029                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     0.50% 0.50%   0.50%     0.50%                      
Debt instrument, principal amount                           ¥ 12,600     ¥ 12,600                      
.843% senior notes due December 2031                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     0.843% 0.843%   0.843%     0.843%                      
Debt instrument, principal amount                           ¥ 9,300     ¥ 9,300                      
.934% senior notes due December 2034                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     0.934% 0.934%   0.934%     0.934%                      
Debt instrument, principal amount                           ¥ 9,800     ¥ 9,800                      
1.122% senior notes due December 2039                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     1.122% 1.122%   1.122%     1.122%                      
Debt instrument, principal amount                           ¥ 6,300     ¥ 6,300                      
Yen-denominated loans                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, principal amount                                   ¥ 30,000                    
Yen-denominated loan variable interest rate due September 2026                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     0.41% 0.43%   0.41%     0.43%                      
Debt instrument, description of variable rate basis         bears interest at a rate per annum equal to the Tokyo interbank market rate (TIBOR), or alternate TIBOR, if applicable, plus the applicable TIBOR margin                                              
Debt instrument, principal amount                           ¥ 5,000     ¥ 5,000 5,000                    
Yen-denominated loan variable interest rate due September 2029                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     0.56% 0.58%   0.56%     0.58%                      
Debt instrument, description of variable rate basis         bears interest at a rate per annum equal to the TIBOR, or alternate TIBOR, if applicable, plus the applicable TIBOR margin                                              
Debt instrument, principal amount                           ¥ 25,000     ¥ 25,000 ¥ 25,000                    
.963% subordinated bonds due April 2049                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate 0.963%                   0.963% 0.963%   0.963%     0.963%                      
Debt instrument, description of variable rate basis These bonds bear interest at a fixed rate of .963% per annum and then at six-month Euro Yen LIBOR plus an applicable spread on and after the day immediately following April 18, 2024.                                                      
Debt instrument, principal amount ¥ 30,000                         ¥ 30,000     ¥ 30,000                      
4.750% senior notes due January 2049                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate           4.75%         4.75% 4.75%   4.75%     4.75%   4.75%                  
Debt instrument, redemption, description           These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 25 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.                                            
Debt instrument, principal amount | $           $ 550                                            
1.159% senior notes due October 2030                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate           1.159%         1.159% 1.159%   1.159%     1.159%   1.159%                  
Debt instrument, principal amount                           ¥ 29,300     ¥ 29,300   ¥ 29,300                  
1.488% senior notes due October 2033                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate           1.488%         1.488% 1.488%   1.488%     1.488%   1.488%                  
Debt instrument, principal amount                           ¥ 15,200     ¥ 15,200   ¥ 15,200                  
1.750% senior notes due October 2038                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate           1.75%         1.75% 1.75%   1.75%     1.75%   1.75%                  
Debt instrument, principal amount                           ¥ 8,900     ¥ 8,900   ¥ 8,900                  
2.108% subordinated notes due October 2047                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate             2.108%       2.108% 2.108%   2.108%     2.108%                      
Debt instrument, redemption, description             The debentures are redeemable (i) at any time, in whole but not in part, upon the occurrence of certain tax events or certain rating agency events, as specified in the indenture governing the terms of the debentures or (ii) on or after October 23, 2027, in whole or in part, at a redemption price equal to their principal amount plus accrued and unpaid interest to, but excluding, the date of redemption.                                          
Debt instrument, interest rate terms             The debentures bear interest at an initial rate of 2.108% per annum through October 22, 2027, or earlier redemption. Thereafter, the rate of the interest of the debentures will be reset every five years at a rate of interest equal to the then-current JPY 5-year Swap Offered Rate plus 205 basis points.                                          
Debt instrument, principal amount             ¥ 60,000             ¥ 60,000     ¥ 60,000                      
.932% senior notes due January 2027                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     0.932% 0.932%   0.932%     0.932%         0.932%            
Debt instrument, principal amount                           ¥ 60,000     ¥ 60,000         ¥ 60,000            
2.875% senior notes due October 2026                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     2.875% 2.875%   2.875%     2.875%       2.875%              
Debt instrument, principal amount | $                                         $ 300              
4.00% senior noted due October 2046                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     4.00% 4.00%   4.00%     4.00%       4.00%              
Debt instrument, principal amount | $                                         $ 400              
3.25% senior notes due March 2025                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     3.25% 3.25%   3.25%     3.25%           3.25% 3.25%        
Debt instrument effective principal amount after cross currency swap                                               ¥ 55,000        
Debt instrument, principal amount | $                                             $ 450          
Debt instrument, effective interest rate                                             0.82% 0.82%        
3.625% senior notes due November 2024                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                 3.625%   3.625% 3.625%   3.625%     3.625%               3.625%      
Debt instrument, redemption, description                 These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the treasury rate plus 20 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.                                      
Debt instrument effective principal amount after cross currency swap                                                 ¥ 85,300      
Debt instrument, principal amount | $                 $ 750                                      
Debt instrument, effective interest rate                 1.00%                               1.00%      
3.625% senior notes paid May 2021                                                        
Debt Instrument [Line Items]                                                        
Repayments of debt | $   $ 700                                                    
Debt instrument, interest rate   3.625%               3.625% 3.625% 3.625%   3.625%     3.625%                 3.625%    
Debt instrument, redemption, description                   These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the treasury rate plus 20 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.                                    
Debt instrument effective principal amount after cross currency swap                                                   ¥ 69,800    
Debt instrument, principal amount | $                   $ 700                                    
Debt instrument, effective interest rate                   1.50%                               1.50%    
Expense on extinguishment of debt | $                     $ 48                                  
4.00% senior notes paid January 2020                                                        
Debt Instrument [Line Items]                                                        
Expense on extinguishment of debt | $                       $ 15                                
6.90% senior notes due December 2039                                                        
Debt Instrument [Line Items]                                                        
Repayments of debt | $               $ 176                                        
Debt instrument, interest rate                     6.90% 6.90%   6.90%     6.90%     6.90%                
Debt instrument, principal amount | $                                                       $ 400
6.45% senior notes due August 2040                                                        
Debt Instrument [Line Items]                                                        
Repayments of debt | $               193                                        
Debt instrument, interest rate                     6.45% 6.45%   6.45%     6.45%     6.45%                
Debt instrument, principal amount | $                                                     $ 450  
Senior Notes due 2039 and 2040                                                        
Debt Instrument [Line Items]                                                        
Expense on extinguishment of debt | $               $ 137                                        
Senior notes                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, principal amount                             ¥ 82,000 ¥ 57,000 ¥ 38,000   ¥ 53,400   $ 700              
Notes Payable                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, debt default, amount | $                     $ 0 $ 0                                
.633% senior notes due April 2031                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     0.633% 0.633%   0.633% 0.633%   0.633%                      
Debt instrument, principal amount                           ¥ 30,000 ¥ 30,000   ¥ 30,000                      
.844% senior notes due April 2033                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     0.844% 0.844%   0.844% 0.844%   0.844%                      
Debt instrument, principal amount                           ¥ 12,000 ¥ 12,000   ¥ 12,000                      
1.039% senior notes due April 2036                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     1.039% 1.039%   1.039% 1.039%   1.039%                      
Debt instrument, principal amount                           ¥ 10,000 ¥ 10,000   ¥ 10,000                      
1.264% senior notes due April 2041                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     1.264% 1.264%   1.264% 1.264%   1.264%                      
Debt instrument, principal amount                           ¥ 10,000 ¥ 10,000   ¥ 10,000                      
1.560% senior notes due April 2051                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate                     1.56% 1.56%   1.56% 1.56%   1.56%                      
Debt instrument, principal amount                           ¥ 20,000 ¥ 20,000                          
1.125% senior notes due March 2026                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, interest rate     1.125%               1.125% 1.125%   1.125%   1.125% 1.125%                      
Debt instrument, redemption, description     These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 10 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.                                                  
Debt instrument, principal amount | $     $ 400                                                  
Lower Limit | Yen-denominated loan variable interest rate due September 2026                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, basis spread on variable rate         0.30%                                              
Lower Limit | Yen-denominated loan variable interest rate due September 2029                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, basis spread on variable rate         0.45%                                              
Upper Limit | Yen-denominated loan variable interest rate due September 2026                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, basis spread on variable rate         0.70%                                              
Upper Limit | Yen-denominated loan variable interest rate due September 2029                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, basis spread on variable rate         1.00%                                              
Line of Credit                                                        
Debt Instrument [Line Items]                                                        
Debt instrument, debt default, amount | $                     $ 0 $ 0                                
v3.22.0.1
NOTES PAYABLE AND LEASE OBLIGATIONS - Summary of Notes Payable (Detail 1) - USD ($)
$ in Millions
Dec. 31, 2021
May 31, 2021
Apr. 30, 2021
Mar. 31, 2021
Dec. 31, 2020
Apr. 30, 2020
Apr. 12, 2019
Oct. 31, 2018
Dec. 31, 2017
Oct. 31, 2017
Sep. 30, 2017
Jan. 31, 2017
Mar. 31, 2016
Nov. 30, 2014
Jun. 30, 2013
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 7,956       $ 7,899                    
Finance lease, liability 12       11                    
Operating lease, liability 105       143                    
3.625% senior notes paid May 2021                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 0       $ 698                    
Debt Instrument, Interest Rate, Stated Percentage 3.625% 3.625%     3.625%                   3.625%
3.625% senior notes due November 2024                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 748       $ 747                    
Debt Instrument, Interest Rate, Stated Percentage 3.625%       3.625%                 3.625%  
3.25% senior notes due March 2025                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 448       $ 448                    
Debt Instrument, Interest Rate, Stated Percentage 3.25%       3.25%               3.25%    
1.125% senior notes due March 2026                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 397       $ 0                    
Debt Instrument, Interest Rate, Stated Percentage 1.125%     1.125% 1.125%                    
2.875% senior notes due October 2026                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 298       $ 298                    
Debt Instrument, Interest Rate, Stated Percentage 2.875%       2.875%           2.875%        
3.60% senior notes due April 2030                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 991       $ 990                    
Debt Instrument, Interest Rate, Stated Percentage 3.60%       3.60% 3.60%                  
6.90% senior notes due December 2039                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 221       $ 221                    
Debt Instrument, Interest Rate, Stated Percentage 6.90%       6.90%       6.90%            
6.45% senior notes due August 2040                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 255       $ 254                    
Debt Instrument, Interest Rate, Stated Percentage 6.45%       6.45%       6.45%            
4.00% senior noted due October 2046                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 394       $ 394                    
Debt Instrument, Interest Rate, Stated Percentage 4.00%       4.00%           4.00%        
4.750% senior notes due January 2049                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 541       $ 541                    
Debt Instrument, Interest Rate, Stated Percentage 4.75%       4.75%     4.75%              
.300% senior notes due September 2025                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 107       $ 119                    
Debt Instrument, Interest Rate, Stated Percentage 0.30%     0.30%                      
.932% senior notes due January 2027                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 520       $ 578                    
Debt Instrument, Interest Rate, Stated Percentage 0.932%       0.932%             0.932%      
.500% senior notes due December 2029                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 109       $ 121                    
Debt Instrument, Interest Rate, Stated Percentage 0.50%       0.50%                    
.550% senior notes due March 2030                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 115       $ 127                    
Debt Instrument, Interest Rate, Stated Percentage 0.55%     0.55%                      
1.159% senior notes due October 2030                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 254       $ 282                    
Debt Instrument, Interest Rate, Stated Percentage 1.159%       1.159%     1.159%              
.633% senior notes due April 2031                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 259       $ 0                    
Debt Instrument, Interest Rate, Stated Percentage 0.633%   0.633%   0.633%                    
.843% senior notes due December 2031                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 81       $ 90                    
Debt Instrument, Interest Rate, Stated Percentage 0.843%       0.843%                    
.750% senior notes due March 2032                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 179       $ 198                    
Debt Instrument, Interest Rate, Stated Percentage 0.75%     0.75% 0.75%                    
.844% senior notes due April 2033                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 104       $ 0                    
Debt Instrument, Interest Rate, Stated Percentage 0.844%   0.844%   0.844%                    
1.488% senior notes due October 2033                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 131       $ 146                    
Debt Instrument, Interest Rate, Stated Percentage 1.488%       1.488%     1.488%              
.934% senior notes due December 2034                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 85       $ 94                    
Debt Instrument, Interest Rate, Stated Percentage 0.934%       0.934%                    
.830% senior notes due March 2035                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 91       $ 101                    
Debt Instrument, Interest Rate, Stated Percentage 0.83%     0.83% 0.83%                    
1.039% senior notes due April 2036                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 86       $ 0                    
Debt Instrument, Interest Rate, Stated Percentage 1.039%   1.039%   1.039%                    
1.750% senior notes due October 2038                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 77       $ 85                    
Debt Instrument, Interest Rate, Stated Percentage 1.75%       1.75%     1.75%              
1.122% senior notes due December 2039                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 54       $ 61                    
Debt Instrument, Interest Rate, Stated Percentage 1.122%       1.122%                    
1.264% senior notes due April 2041                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 86       $ 0                    
Debt Instrument, Interest Rate, Stated Percentage 1.264%   1.264%   1.264%                    
2.108% subordinated notes due October 2047                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 517       $ 575                    
Debt Instrument, Interest Rate, Stated Percentage 2.108%       2.108%         2.108%          
.963% subordinated bonds due April 2049                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 260       $ 289                    
Debt Instrument, Interest Rate, Stated Percentage 0.963%       0.963%   0.963%                
1.560% senior notes due April 2051                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 172       $ 0                    
Debt Instrument, Interest Rate, Stated Percentage 1.56%   1.56%   1.56%                    
Yen-denominated loan variable interest rate due September 2026                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 43       $ 48                    
Debt Instrument, Interest Rate, Stated Percentage 0.41%       0.43%                    
Yen-denominated loan variable interest rate due September 2029                              
Debt Instrument [Line Items]                              
Notes payable and lease obligations $ 216       $ 240                    
Debt Instrument, Interest Rate, Stated Percentage 0.56%       0.58%                    
v3.22.0.1
NOTES PAYABLE AND LEASE OBLIGATIONS - Summary of Notes Payable (Detail 2)
¥ in Millions, $ in Millions
Dec. 31, 2021
JPY (¥)
May 31, 2021
Apr. 30, 2021
JPY (¥)
Mar. 31, 2021
JPY (¥)
Mar. 31, 2021
USD ($)
Dec. 31, 2020
JPY (¥)
Sep. 30, 2020
JPY (¥)
Apr. 30, 2020
USD ($)
Apr. 12, 2019
JPY (¥)
Oct. 31, 2018
JPY (¥)
Oct. 31, 2018
USD ($)
Dec. 31, 2017
Oct. 31, 2017
JPY (¥)
Sep. 30, 2017
USD ($)
Jan. 31, 2017
JPY (¥)
Mar. 31, 2016
USD ($)
Nov. 30, 2014
USD ($)
Jun. 30, 2013
USD ($)
Aug. 31, 2010
USD ($)
Dec. 31, 2009
USD ($)
3.625% senior notes paid May 2021                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 3.625% 3.625%       3.625%                       3.625%    
Debt instrument, principal amount | $                                   $ 700    
3.625% senior notes due November 2024                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 3.625%         3.625%                     3.625%      
Debt instrument, principal amount | $                                 $ 750      
3.25% senior notes due March 2025                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 3.25%         3.25%                   3.25%        
Debt instrument, principal amount | $                               $ 450        
1.125% senior notes due March 2026                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 1.125%     1.125% 1.125% 1.125%                            
Debt instrument, principal amount | $         $ 400                              
2.875% senior notes due October 2026                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 2.875%         2.875%               2.875%            
Debt instrument, principal amount | $                           $ 300            
3.60% senior notes due April 2030                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 3.60%         3.60%   3.60%                        
Debt instrument, principal amount | $               $ 1,000                        
6.90% senior notes due December 2039                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 6.90%         6.90%           6.90%                
Debt instrument, principal amount | $                                       $ 400
6.45% senior notes due August 2040                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 6.45%         6.45%           6.45%                
Debt instrument, principal amount | $                                     $ 450  
4.00% senior noted due October 2046                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 4.00%         4.00%               4.00%            
Debt instrument, principal amount | $                           $ 400            
4.750% senior notes due January 2049                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 4.75%         4.75%       4.75% 4.75%                  
Debt instrument, principal amount | $                     $ 550                  
.300% senior notes due September 2025                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.30%     0.30% 0.30%                              
Debt instrument, principal amount ¥ 12,400     ¥ 12,400                                
.932% senior notes due January 2027                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.932%         0.932%                 0.932%          
Debt instrument, principal amount ¥ 60,000         ¥ 60,000                 ¥ 60,000          
.500% senior notes due December 2029                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.50%         0.50%                            
Debt instrument, principal amount ¥ 12,600         ¥ 12,600                            
.550% senior notes due March 2030                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.55%     0.55% 0.55%                              
Debt instrument, principal amount ¥ 13,300     ¥ 13,300                                
1.159% senior notes due October 2030                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 1.159%         1.159%       1.159% 1.159%                  
Debt instrument, principal amount ¥ 29,300         ¥ 29,300       ¥ 29,300                    
.633% senior notes due April 2031                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.633%   0.633%     0.633%                            
Debt instrument, principal amount ¥ 30,000   ¥ 30,000     ¥ 30,000                            
.843% senior notes due December 2031                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.843%         0.843%                            
Debt instrument, principal amount ¥ 9,300         ¥ 9,300                            
.750% senior notes due March 2032                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.75%     0.75% 0.75% 0.75%                            
Debt instrument, principal amount ¥ 20,700     ¥ 20,700   ¥ 20,700                            
.844% senior notes due April 2033                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.844%   0.844%     0.844%                            
Debt instrument, principal amount ¥ 12,000   ¥ 12,000     ¥ 12,000                            
1.488% senior notes due October 2033                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 1.488%         1.488%       1.488% 1.488%                  
Debt instrument, principal amount ¥ 15,200         ¥ 15,200       ¥ 15,200                    
.934% senior notes due December 2034                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.934%         0.934%                            
Debt instrument, principal amount ¥ 9,800         ¥ 9,800                            
.830% senior notes due March 2035                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.83%     0.83% 0.83% 0.83%                            
Debt instrument, principal amount ¥ 10,600     ¥ 10,600   ¥ 10,600                            
1.039% senior notes due April 2036                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 1.039%   1.039%     1.039%                            
Debt instrument, principal amount ¥ 10,000   ¥ 10,000     ¥ 10,000                            
1.750% senior notes due October 2038                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 1.75%         1.75%       1.75% 1.75%                  
Debt instrument, principal amount ¥ 8,900         ¥ 8,900       ¥ 8,900                    
1.122% senior notes due December 2039                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 1.122%         1.122%                            
Debt instrument, principal amount ¥ 6,300         ¥ 6,300                            
1.264% senior notes due April 2041                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 1.264%   1.264%     1.264%                            
Debt instrument, principal amount ¥ 10,000   ¥ 10,000     ¥ 10,000                            
2.108% subordinated notes due October 2047                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 2.108%         2.108%             2.108%              
Debt instrument, principal amount ¥ 60,000         ¥ 60,000             ¥ 60,000              
.963% subordinated bonds due April 2049                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.963%         0.963%     0.963%                      
Debt instrument, principal amount ¥ 30,000         ¥ 30,000     ¥ 30,000                      
1.560% senior notes due April 2051                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 1.56%   1.56%     1.56%                            
Debt instrument, principal amount ¥ 20,000   ¥ 20,000                                  
Yen-denominated loan variable interest rate due September 2026                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.41%         0.43%                            
Debt instrument, principal amount ¥ 5,000         ¥ 5,000 ¥ 5,000                          
Yen-denominated loan variable interest rate due September 2029                                        
Debt Instrument [Line Items]                                        
Debt instrument, interest rate 0.56%         0.58%                            
Debt instrument, principal amount ¥ 25,000         ¥ 25,000 ¥ 25,000                          
v3.22.0.1
NOTES PAYABLE AND LEASE OBLIGATIONS - Aggregate Contractual Maturities of Notes Payable (Detail)
$ in Millions
Dec. 31, 2021
USD ($)
Debt Disclosure [Abstract]  
2022 $ 0
2023 0
2024 750
2025 558
2026 743
Thereafter 5,847
Total $ 7,898
v3.22.0.1
NOTES PAYABLE AND LEASE OBLIGATIONS - Contractual Maturities of Leases (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Operating Leases    
2021 $ 48  
2022 16  
2023 11  
2024 11  
2025 8  
Thereafter 17  
Total lease payments 111  
Less: Interest 6  
Present value of lease liabilities 105 $ 143
Finance Leases    
2021 4  
2022 3  
2023 3  
2024 2  
2025 0  
Thereafter 0  
Total lease payments 12  
Less: Interest 0  
Present value of lease liabilities 12 $ 11
Total    
2021 52  
2022 19  
2023 14  
2024 13  
2025 8  
Thereafter 17  
Total lease payments 123  
Less: Interest 6  
Present value of lease liabilities $ 117  
Finance lease, liability Notes payable and lease obligations Notes payable and lease obligations
Operating lease, liability Notes payable and lease obligations Notes payable and lease obligations
v3.22.0.1
NOTES PAYABLE AND LEASE OBLIGATIONS - Weighted Average Lease Term and Discount Rate (Details)
Dec. 31, 2021
Dec. 31, 2020
Debt Disclosure [Abstract]    
Operating lease, weighted average remaining lease term 6 years 9 months 18 days 6 years 8 months 12 days
Finance lease, weighted average remaining lease term 3 years 6 months 3 years 6 months
Operating lease, weighted average discount rate, percent 2.20% 2.00%
Finance lease, weighted average discount rate, percent 1.40% 1.50%
v3.22.0.1
NOTES PAYABLE AND LEASE OBLIGATIONS - Summary of Lines of Credit (Detail) - 12 months ended Dec. 31, 2021
¥ in Millions, $ in Millions
USD ($)
JPY (¥)
$100 million line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description The rate quoted by the bank and agreed upon at the time of borrowing  
Line of credit facility term 364 days  
Line of credit facility, maximum borrowing capacity $ 100.0  
Line of credit facility, amount outstanding $ 0.0  
100.0 billion yen line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description A rate per annum equal to (a) Tokyo interbank market rate (TIBOR) plus, the alternative applicable TIBOR margin during the availability period from the closing date to the commitment termination date or (b) the TIBOR rate offered by the agent to major banks in yen for the applicable period plus, the applicable alternative TIBOR margin during the term out period  
Line of credit facility term 5 years  
Line of credit facility, maximum borrowing capacity | ¥   ¥ 100,000
Line of credit facility, amount outstanding | ¥   0
$1.0 billion line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description A rate per annum equal to, at the Company's option, either, (a) USD LIBOR for U.S. dollar denominated borrowings or TIBOR for Japanese yen denominated borrowings, in either case adjusted for certain costs or (b) a base rate determined by reference to the highest of (1) the federal funds rate plus 1/2 of 1%, (2) the rate of interest for such day announced by Mizuho Bank, Ltd. as its prime rate, or (3) the eurocurrency rate for an interest period of one month plus 1.00%, in each case plus an applicable margin  
Line of credit facility term 5 years  
Line of credit facility, maximum borrowing capacity $ 1,000.0  
Line of credit facility, amount outstanding $ 0.0  
$50 million line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description A rate per annum equal to, at the Parent Company's option, either (a) a rate determined by reference to USD LIBOR for the interest period relevant to such borrowing or (b) the base rate determined by reference to the highest of (a) the lender's U.S. dollar short-term commercial loan rate, (b) the federal funds rate plus 1/2 of 1% and (c) USD one-month LIBOR plus 1%. USD LIBOR is subject to replacement with Secured Overnight Financing Rate (SOFR) under certain circumstances  
Line of credit facility, maximum borrowing capacity $ 50.0  
Line of credit facility, amount outstanding $ 0.0  
$250 million line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description USD three-month LIBOR plus 75 basis points per annum  
Line of credit facility term 364 days  
Line of credit facility, maximum borrowing capacity $ 250.0  
Line of credit facility, amount outstanding $ 0.0  
Debt instrument, term 3 months  
50.0 billion yen line of credit expiring April 2021    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description Three-month TIBOR plus 70 basis points per annum  
Line of credit facility term 364 days  
Line of credit facility, maximum borrowing capacity | ¥   50,000
Line of credit facility, amount outstanding | ¥   0
Debt instrument, term 3 months  
50.0 billion yen line of credit expiring November 2021    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description Three-month TIBOR plus 70 basis points per annum  
Line of credit facility term 364 days  
Line of credit facility, maximum borrowing capacity | ¥   50,000
Line of credit facility, amount outstanding | ¥   0
Debt instrument, term 3 months  
$25 million line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description USD three-month LIBOR plus 75 basis points per annum  
Line of credit facility term 364 days  
Line of credit facility, maximum borrowing capacity $ 25.0  
Line of credit facility, amount outstanding $ 0.0  
Debt instrument, term 3 months  
$15 million line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description USD three-month LIBOR plus 75 basis points per annum  
Line of credit facility term 364 days  
Line of credit facility, maximum borrowing capacity $ 15.0  
Line of credit facility, amount outstanding $ 0.0  
Debt instrument, term 3 months  
$300 thousand line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description USD three-month LIBOR plus 75 basis points per annum  
Line of credit facility term 364 days  
Line of credit facility, maximum borrowing capacity $ 0.3  
Line of credit facility, amount outstanding $ 0.0  
Debt instrument, term 3 months  
500 hundred million yen line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description A rate per annum equal to the short-term prime lending rates of banks appearing on the website for the Bank of Japan on the first day of the applicable period  
Line of credit facility term 364 days  
Line of credit facility, maximum borrowing capacity | ¥   500
Line of credit facility, amount outstanding | ¥   350
Nine hundred million yen line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description A rate per annum equal to the short-term prime lending rates of banks appearing on the website for the Bank of Japan on the first day of the applicable period  
Line of credit facility term 364 days  
Line of credit facility, maximum borrowing capacity | ¥   900
Line of credit facility, amount outstanding | ¥   0
Six hundred million yen line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description A rate per annum equal to the short-term prime lending rates of banks appearing on the website for the Bank of Japan on the first day of the applicable period  
Line of credit facility term 364 days  
Line of credit facility, maximum borrowing capacity | ¥   600
Line of credit facility, amount outstanding | ¥   ¥ 0
Thirty million dollar line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, interest rate description USD three-month LIBOR plus 75 basis points per annum  
Line of credit facility term 364 days  
Line of credit facility, maximum borrowing capacity $ 30.0  
Line of credit facility, amount outstanding $ 0.0  
Lower Limit | 100.0 billion yen line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, commitment fee percentage 0.30%  
Lower Limit | $1.0 billion line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, commitment fee percentage 0.085%  
Upper Limit | $100 million line of credit    
Line of Credit Facility [Line Items]    
Debt instrument, term 3 months  
Upper Limit | 100.0 billion yen line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, commitment fee percentage 0.50%  
Upper Limit | $1.0 billion line of credit    
Line of Credit Facility [Line Items]    
Line of credit facility, commitment fee percentage 0.225%  
Upper Limit | $50 million line of credit    
Line of Credit Facility [Line Items]    
Debt instrument, term 3 months  
v3.22.0.1
INCOME TAXES - Additional Information (Detail) - USD ($)
$ in Millions
 1 Months Ended 12 Months Ended
Sep. 30, 2020
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Income Taxes [Line Items]        
Japan Tax Rate   28.00% 28.00% 28.00%
U.S. federal statutory corporate income tax rate   21.00% 21.00% 21.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax Asset (Liability) $ (1,400)      
Non-life operating loss carryforwards, limitations   only 35% of non-life operating losses can be offset against life insurance taxable income each year    
Non-life operating loss carryforwards   $ 56    
Unrecognized tax benefit, deductibility highly certain, timing uncertain   0 $ 15  
Unrecognized tax benefits, permanent uncertainties   5    
Unrecognized tax benefits, interest and penalties expense   1    
Unrecognized tax benefits, accrued interest and penalties   0 $ 3  
Capital Loss Carryforward        
Income Taxes [Line Items]        
Tax credit carryforward, amount   0    
Foreign Tax Credit        
Income Taxes [Line Items]        
Tax credit carryforward, amount   31    
Tax Year 2030 | Foreign Tax Credit        
Income Taxes [Line Items]        
Tax credit carryforward, amount   3    
Tax Year 2031 | Foreign Tax Credit        
Income Taxes [Line Items]        
Tax credit carryforward, amount   $ 28    
v3.22.0.1
INCOME TAXES - Components of Income Tax Expense (Benefit) Applicable to Pretax Earnings (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Reconciliation of Provision of Income Taxes [Line Items]      
Current $ 1,095 $ 794 $ 806
Deferred (98) (1,413) 335
Total income tax expense 997 (619) 1,141
Aflac Japan      
Reconciliation of Provision of Income Taxes [Line Items]      
Current 884 822 737
Deferred 251 (28) 183
Total income tax expense 1,135 794 920
Aflac U.S.      
Reconciliation of Provision of Income Taxes [Line Items]      
Current 211 (28) 69
Deferred (349) (1,385) 152
Total income tax expense $ (138) $ (1,413) $ 221
v3.22.0.1
INCOME TAXES - Principal Reasons for Differences and Related Tax Effects where Income Tax Expense Varies from Amount Computed by Applying Expected United States Tax Rate to Pretax Earnings (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Income Tax Disclosure [Abstract]      
Income taxes based on U.S. statutory rates $ 1,118 $ 873 $ 933
Foreign rate differential 0 0 229
Valuation allowance release 0 (1,411) 0
Other, net (121) (81) (21)
Total income tax expense $ 997 $ (619) $ 1,141
v3.22.0.1
INCOME TAXES - Total Income Tax Expense (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Income Tax Disclosure [Abstract]      
Statements of earnings $ 997 $ (619) $ 1,141
Other comprehensive income (loss):      
Unrealized foreign currency translation gains (losses) during period 15 (3) 27
Unrealized gains (losses) on investment securities:      
Unrealized holding gains (losses) on investment securities during period (194) 223 1,532
Reclassification adjustment for realized (gains) losses on investment securities included in net earnings (7) 33 5
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax 1 0 (3)
Pension liability adjustment during period 30 (2) (18)
Total income tax expense (benefit) related to items of other comprehensive income (loss) (155) 251 1,543
Total income taxes $ 842 $ (368) $ 2,684
v3.22.0.1
INCOME TAXES - Income Tax Effects of Temporary Differences that Gave Rise to Deferred Income Tax Assets and Liabilities (Detail) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Deferred income tax liabilities:    
Deferred policy acquisition costs $ 3,262 $ 3,663
Unrealized gains and other basis differences on investments 5,313 5,227
Foreign currency gain on Aflac Japan 0 70
Premiums receivable 66 112
Policy benefit reserves 3,578 3,834
Total deferred income tax liabilities 12,219 12,906
Deferred income tax assets:    
Unfunded retirement benefits 7 9
Other accrued expenses 38 37
Policy and contract claims 794 868
Foreign currency loss on Aflac Japan 91 0
Deferred compensation 104 137
Capital loss carryforwards 0 12
Depreciation 230 202
Anticipatory foreign tax credit 5,883 5,972
Deferred foreign tax credit 701 647
Other 163 326
Total deferred income tax assets 8,011 8,210
Net deferred income tax liability 4,208 4,696
Current income tax liability 131  
Current income tax asset   (35)
Total income tax liability $ 4,339 $ 4,661
v3.22.0.1
INCOME TAXES - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]    
Balance, beginning of year $ 19 $ 17
Additions for tax positions of prior years 1 2
Reductions for tax positions of prior years (15) 0
Balance, end of year $ 5 $ 19
v3.22.0.1
SHAREHOLDERS' EQUITY - Additional Information (Detail)
shares in Millions, $ in Millions
 12 Months Ended
Dec. 31, 2021
USD ($)
votesPerShare
shares
Dec. 31, 2020
USD ($)
shares
Dec. 31, 2019
USD ($)
shares
Aug. 31, 2020
shares
Stockholders Equity Note [Line Items]        
Common stock, share repurchase, dollar amount | $ $ 2,301 $ 1,537 $ 1,627  
Remaining common stock available for purchase under share repurchase authorizations 55.8      
Common stock, voting rights are generally entitled to one vote per share until they have been held by the same beneficial owner for a continuous period of 48 months, at which time they become entitled to 10 votes per share      
Common stock, votes per share | votesPerShare 1      
Common stock, votes per share holding period 48 months      
Common stock, votes per share after required holding period. | votesPerShare 10      
Share Repurchase Program        
Stockholders Equity Note [Line Items]        
Stock acquired under share repurchase program, shares 43.3 37.9 32.0  
Common stock, share repurchase, dollar amount | $ $ 2,300 $ 1,500 $ 1,600  
Share Repurchase Authorization 2020        
Stockholders Equity Note [Line Items]        
Remaining common stock available for purchase under share repurchase authorizations       100.0
v3.22.0.1
SHAREHOLDERS' EQUITY - Reconciliation of Number of Shares of Common Stock (Detail) - shares
shares in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Common Stock Issued [Roll Forward]      
Balance, beginning of period 1,351,018 1,349,309 1,347,540
Exercise of stock options and issuance of restricted shares 1,721 1,709 1,769
Balance, end of period 1,352,739 1,351,018 1,349,309
Treasury Stock [Roll Forward]      
Balance, beginning of period 658,564 622,516 592,254
Exercise of stock options (896) (638) (1,584)
Balance, end of period 700,607 658,564 622,516
Shares outstanding, end of period 652,132 692,454 726,793
Treasury Stock      
Treasury Stock [Roll Forward]      
Share repurchase program 43,327 37,899 31,994
Other purchases 437 542 592
Shares issued to AFL Stock Plan (1,216) (2,021) (1,610)
Exercise of stock options (275) (121) (418)
Other dispositions (230) (251) (296)
v3.22.0.1
SHAREHOLDERS' EQUITY - Anti-Dilutive Share-Based Awards Excluded from Calculation of Diluted Earnings Per Share (Detail) - shares
shares in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Stockholders' Equity Note [Abstract]      
Anti-dilutive share-based awards 0 687 6
v3.22.0.1
SHAREHOLDERS' EQUITY - Weighted-Average Shares Used in Calculating Earnings Per Share (Details) - shares
shares in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Stockholders' Equity Note [Abstract]      
Weighted-average outstanding shares used for calculating basic EPS 673,617 713,702 742,414
Dilutive effect of share-based awards 3,112 2,490 4,016
Weighted-average outstanding shares used for calculating diluted EPS 676,729 716,192 746,430
v3.22.0.1
SHAREHOLDERS' EQUITY - Changes in Accumulated Other Comprehensive Income (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period $ 8,934 $ 6,615 $ 2,151
Other comprehensive income loss before reclassifications net of tax (1,550) 1,322 4,466
Amounts reclassified from accumulated other comprehensive income (loss) net of tax 9 149 (2)
Other comprehensive income (loss), net of tax (1,541) 1,471 4,464
Balance, end of period 7,393 8,934 6,615
Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjustment      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period   848  
Balance, end of period     848
Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjusted balance      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period   7,463  
Balance, end of period     7,463
Unrealized foreign currency translation gains (losses)      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period (1,109) (1,623) (1,847)
Other comprehensive income loss before reclassifications net of tax (904) 514 224
Amounts reclassified from accumulated other comprehensive income (loss) net of tax 0 0 0
Other comprehensive income (loss), net of tax (904) 514 224
Balance, end of period (2,013) (1,109) (1,623)
Unrealized foreign currency translation gains (losses) | Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjustment      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period   0  
Balance, end of period     0
Unrealized foreign currency translation gains (losses) | Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjusted balance      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period   (1,623)  
Balance, end of period     (1,623)
Unrealized gains (losses) on fixed maturity securities      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period 10,361 8,548 4,234
Other comprehensive income loss before reclassifications net of tax (735) 839 4,327
Amounts reclassified from accumulated other comprehensive income (loss) net of tax (24) 126 (13)
Other comprehensive income (loss), net of tax (759) 965 4,314
Balance, end of period 9,602 10,361 8,548
Unrealized gains (losses) on fixed maturity securities | Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjustment      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period   848  
Balance, end of period     848
Unrealized gains (losses) on fixed maturity securities | Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjusted balance      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period   9,396  
Balance, end of period     9,396
Unrealized gains (losses) on derivatives      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period (34) (33) (24)
Other comprehensive income loss before reclassifications net of tax (1) (1) (9)
Amounts reclassified from accumulated other comprehensive income (loss) net of tax 5 0 0
Other comprehensive income (loss), net of tax 4 (1) (9)
Balance, end of period (30) (34) (33)
Unrealized gains (losses) on derivatives | Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjustment      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period   0  
Balance, end of period     0
Unrealized gains (losses) on derivatives | Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjusted balance      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period   (33)  
Balance, end of period     (33)
Pension liability adjustment      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period (284) (277) (212)
Other comprehensive income loss before reclassifications net of tax 90 (30) (76)
Amounts reclassified from accumulated other comprehensive income (loss) net of tax 28 23 11
Other comprehensive income (loss), net of tax 118 (7) (65)
Balance, end of period $ (166) (284) (277)
Pension liability adjustment | Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjustment      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period   0  
Balance, end of period     0
Pension liability adjustment | Accounting Standards Update 2019-04 | Cumulative effect, period of adoption, adjusted balance      
Accumulated Other Comprehensive Income [Roll Forward]      
Balance, beginning of period   $ (277)  
Balance, end of period     $ (277)
v3.22.0.1
SHAREHOLDERS' EQUITY - Reclassifications Out of Accumulated Other Comprehensive Income (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Net investment gains (losses) $ 468 $ (270) $ (135)
Net investment income 3,818 3,638 3,578
Acquisition and operating expenses (6,208) (6,192) (5,920)
Total before tax 5,322 4,159 4,445
Income tax (expense) benefit (997) 619 (1,141)
Net of tax $ 4,325 $ 4,778 $ 3,304
U.S. federal statutory corporate income tax rate 21.00% 21.00% 21.00%
Blended statutory income tax rate     26.00%
Reclassification out of Accumulated Other Comprehensive Income      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Net of tax $ (9) $ (149) $ 2
Reclassification out of Accumulated Other Comprehensive Income | Unrealized gains (losses) on available-for-sale securities      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Net investment gains (losses) 31 (159) 18
Income tax (expense) benefit (7) [1] 33 [2] (5) [3]
Net of tax 24 (126) 13
Reclassification out of Accumulated Other Comprehensive Income | Unrealized gains (losses) on derivatives      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Net investment gains (losses) (5)    
Net investment income (1)    
Total before tax (6)    
Income tax (expense) benefit 1    
Net of tax (5)    
Reclassification out of Accumulated Other Comprehensive Income | Pension liability adjustment, actuarial gains (losses)      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Acquisition and operating expenses [4] (35) (32) (15)
Reclassification out of Accumulated Other Comprehensive Income | Pension liability adjustment, prior service (cost) credit      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Acquisition and operating expenses [4] 0 3 0
Reclassification out of Accumulated Other Comprehensive Income | Pension liability adjustment      
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]      
Income tax (expense) benefit 7 [1] 6 [2] 4 [3]
Net of tax $ (28) $ (23) $ (11)
[1] Based on 21% tax rate
[2] Based on 21% tax rate
[3] Based on 26% blended tax rate
[4] These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 14 for additional details).
v3.22.0.1
SHARE-BASED COMPENSATION - Additional Information (Detail) - USD ($)
$ / shares in Units, shares in Thousands, $ in Millions
 1 Months Ended 12 Months Ended
Nov. 30, 2020
Feb. 29, 2020
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Share based compensation arrangement by share-based payment award, options, grants in period, weighted average grant date fair value     $ 0   $ 6.33  
Closing common stock price     $ 58.39      
Aggregate intrinsic value of stock options outstanding     $ 59      
Options outstanding - weighted-average remaining term (Yrs)     3 years 4 months 24 days      
In-the-money stock options exercisable     2,100      
Aggregate intrinsic value of stock options exercisable     $ 59      
Weighted-average remaining term of stock options exercisable (in years)     3 years 4 months 24 days      
Long-Term Incentive Plan            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Share-based compensation arrangement by share-based payment award, maximum number of shares issuable     75,000      
Share-based compensation arrangement by share-based payment award, maximum number of shares issuable other than options and stock appreciation rights     38,000      
Shares available for future grants under the long-term incentive plan     36,700      
Long-term incentive plan awards, term (in years)     10 years      
Long-term incentive plan, vesting period     3 years      
Restricted Stock            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Restricted stock awards, grants in period     1,496 1,544 1,070 [1]  
Total compensation cost not yet recognized, restricted stock awards     $ 35      
Share-based compensation arrangement by share-based payment award, equity instruments other than options, nonvested, number of shares     2,557 2,580 2,715 [1] 3,407
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition     1 year 9 months 18 days      
Performance Based Vesting Condition | Long-Term Incentive Plan            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Long-term incentive plan, vesting period     3 years      
Performance Based Vesting Condition | Restricted Stock            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Long-term incentive plan, vesting period     3 years      
Restricted stock awards, grants in period   454        
Percentage of target award opportunities minimum     0.00%      
Percentage of target award opportunities maximum     200.00%      
Total compensation cost not yet recognized, restricted stock awards     $ 13      
Share-based compensation arrangement by share-based payment award, equity instruments other than options, nonvested, number of shares     1,200      
Performance Based Vesting Condition | Restricted Stock Units            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Long-term incentive plan, vesting period     3 years      
Restricted stock awards, grants in period 26          
Percentage of target award opportunities minimum     0.00%      
Percentage of target award opportunities maximum     200.00%      
[1] This balance has been adjusted to include dividends
v3.22.0.1
SHARE-BASED COMPENSATION - Expense Recognized in Connection with Share-Based Awards (Detail) - USD ($)
$ / shares in Units, $ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]      
Earnings before income taxes $ 5,322 $ 4,159 $ 4,445
Net earnings $ 4,325 $ 4,778 $ 3,304
Net earnings per share:      
Basic (in dollars per share) $ 6.42 $ 6.69 $ 4.45
Diluted (in dollars per share) $ 6.39 $ 6.67 $ 4.43
Share Based Compensation Expense      
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]      
Earnings from continuing operations $ 65 $ 61 $ 59
Earnings before income taxes 65 61 59
Net earnings $ 51 $ 48 $ 46
Net earnings per share:      
Basic (in dollars per share) $ 0.08 $ 0.07 $ 0.06
Diluted (in dollars per share) $ 0.08 $ 0.07 $ 0.06
v3.22.0.1
SHARE-BASED COMPENSATION - Stock Option Activity (Detail) - $ / shares
shares in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Stock Option Shares      
Beginning Balance 3,045 3,706 5,330
Granted 0 59 0
Canceled (4) (82) (40)
Exercised (896) (638) (1,584)
Ending Balance 2,145 3,045 3,706
Weighted-Average Exercise Price Per Share      
Beginning Balance $ 30.25 $ 29.65 $ 28.54
Granted 0.00 35.75 0.00
Canceled 16.93 26.31 27.28
Exercised 28.45 27.82 25.97
Ending Balance $ 31.02 $ 30.25 $ 29.65
v3.22.0.1
SHARE-BASED COMPENSATION - Shares Exercisable (Detail) - shares
shares in Thousands
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Share-based Payment Arrangement [Abstract]      
Shares exercisable, end of year 2,145 2,986 3,553
v3.22.0.1
SHARE-BASED COMPENSATION - Assumptions Used in Valuing Options Granted (Detail) - Employee stock option
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Line Items]      
Expected term (years) 7 years 10 months 24 days 6 years 7 years
Expected volatility 25.60% 24.40% 18.00%
Annual forfeiture rate 3.80% 3.90% 3.90%
Risk-free interest rate 1.00% 2.00% 2.90%
Dividend yield 3.00% 3.30% 2.20%
v3.22.0.1
SHARE-BASED COMPENSATION - Stock Options Outstanding and Exercisable (Detail) - $ / shares
shares in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Range of Exercise Prices Per Share - Lower Range $ 0.00      
Range of Exercise Prices Per Share - Upper Range $ 44.59      
Options Outstanding - Stock Option Shares 2,145 3,045 3,706 5,330
Options outstanding - weighted-average remaining term (Yrs) 3 years 4 months 24 days      
Options Outstanding - Weighted-Average Exercise Price Per Share $ 31.02 $ 30.25 $ 29.65 $ 28.54
Options Exercisable - Stock Option Shares 2,145 2,986 3,553  
Options Exercisable - Weighted-Average Exercise Price Per Share $ 31.02      
$0.00 - $24.75        
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Range of Exercise Prices Per Share - Lower Range 0.00      
Range of Exercise Prices Per Share - Upper Range $ 24.75      
Options Outstanding - Stock Option Shares 336      
Options outstanding - weighted-average remaining term (Yrs) 8 months 12 days      
Options Outstanding - Weighted-Average Exercise Price Per Share $ 24.09      
Options Exercisable - Stock Option Shares 336      
Options Exercisable - Weighted-Average Exercise Price Per Share $ 24.09      
$24.75 - $28.97        
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Range of Exercise Prices Per Share - Lower Range 24.75      
Range of Exercise Prices Per Share - Upper Range $ 28.97      
Options Outstanding - Stock Option Shares 370      
Options outstanding - weighted-average remaining term (Yrs) 3 years 10 months 24 days      
Options Outstanding - Weighted-Average Exercise Price Per Share $ 28.85      
Options Exercisable - Stock Option Shares 370      
Options Exercisable - Weighted-Average Exercise Price Per Share $ 28.85      
$28.97 - $31.21        
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Range of Exercise Prices Per Share - Lower Range 28.97      
Range of Exercise Prices Per Share - Upper Range $ 31.21      
Options Outstanding - Stock Option Shares 718      
Options outstanding - weighted-average remaining term (Yrs) 2 years 9 months 18 days      
Options Outstanding - Weighted-Average Exercise Price Per Share $ 30.74      
Options Exercisable - Stock Option Shares 718      
Options Exercisable - Weighted-Average Exercise Price Per Share $ 30.74      
$31.21 - $36.21        
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Range of Exercise Prices Per Share - Lower Range 31.21      
Range of Exercise Prices Per Share - Upper Range $ 36.21      
Options Outstanding - Stock Option Shares 572      
Options outstanding - weighted-average remaining term (Yrs) 4 years 8 months 12 days      
Options Outstanding - Weighted-Average Exercise Price Per Share $ 34.36      
Options Exercisable - Stock Option Shares 572      
Options Exercisable - Weighted-Average Exercise Price Per Share $ 34.36      
$36.21 - $44.59        
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]        
Range of Exercise Prices Per Share - Lower Range 36.21      
Range of Exercise Prices Per Share - Upper Range $ 44.59      
Options Outstanding - Stock Option Shares 149      
Options outstanding - weighted-average remaining term (Yrs) 5 years 9 months 18 days      
Options Outstanding - Weighted-Average Exercise Price Per Share $ 40.57      
Options Exercisable - Stock Option Shares 149      
Options Exercisable - Weighted-Average Exercise Price Per Share $ 40.57      
v3.22.0.1
SHARE-BASED COMPENSATION - Summary of Stock Option Activity (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Share-based Payment Arrangement [Abstract]      
Total intrinsic value of options exercised $ 21 $ 11 $ 38
Cash received from options exercised 26 18 40
Tax benefit realized as a result of options exercised and restricted stock releases $ 17 $ 18 $ 34
v3.22.0.1
SHARE-BASED COMPENSATION - Key Assumptions Used to Value PBRS (Details) - Performance Based Vesting Condition - Restricted Stock
 12 Months Ended
Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Expected volatility (based on Aflac Inc. and peer group historical daily stock price) 36.75%
Expected life from grant date (years) 2 years 10 months 24 days
Risk-free interest rate (based on U.S. Treasury yields at the date of grant) 0.18%
v3.22.0.1
SHARE-BASED COMPENSATION - Restricted Stock Activity (Detail) - Restricted Stock - $ / shares
shares in Thousands
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Shares      
Beginning balance 2,580 2,715 [1] 3,407
Granted 1,496 1,544 1,070 [1]
Canceled (148) (119) (39) [1]
Vested (1,371) (1,560) (1,723) [1]
Ending Balance 2,557 2,580 2,715 [1]
Weighted-Average Grant-Date Fair Value Per Share      
Beginning balance $ 48.57 $ 43.74 [1] $ 36.52
Granted 47.87 45.88 49.68 [1]
Canceled 49.00 49.27 41.60 [1]
Vested 45.80 35.23 32.50 [1]
Ending Balance $ 49.38 $ 48.57 $ 43.74 [1]
[1] This balance has been adjusted to include dividends
v3.22.0.1
STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS - Additional Information (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Aflac Japan    
Statutory Accounting Practices [Line Items]    
Capital and surplus, statutory accounting practices of the state or country basis $ 9,800 $ 9,000
Aflac    
Statutory Accounting Practices [Line Items]    
Amount available for dividend distribution without prior approval from regulatory agency 1,100  
Dividends declared 654  
Aflac New York    
Statutory Accounting Practices [Line Items]    
Dividends declared $ 75  
v3.22.0.1
STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS - Capital and Surplus Based on Statutory Accounting Practices (Details) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Aflac    
Statutory Accounting Practices [Line Items]    
Capital and surplus, NAIC basis $ 2,627 $ 2,088
CAIC    
Statutory Accounting Practices [Line Items]    
Capital and surplus, NAIC basis 244 271
TOIC    
Statutory Accounting Practices [Line Items]    
Capital and surplus, NAIC basis 57 61
Aflac New York    
Statutory Accounting Practices [Line Items]    
Capital and surplus, NAIC basis $ 360 $ 352
v3.22.0.1
STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS - Net Income (Loss) Based on Statutory Accounting Practices (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Aflac      
Statutory Accounting Practices [Line Items]      
Net income (loss), statutory accounting practices $ 1,146 $ 872 $ 864
CAIC      
Statutory Accounting Practices [Line Items]      
Net income (loss), statutory accounting practices (30) 1 (16)
TOIC      
Statutory Accounting Practices [Line Items]      
Net income (loss), statutory accounting practices (27) (24) (2)
Aflac New York      
Statutory Accounting Practices [Line Items]      
Net income (loss), statutory accounting practices $ 83 $ 75 $ 75
v3.22.0.1
STATUTORY ACCOUNTING AND DIVIDEND RESTRICTIONS - Profit Remittances by Aflac Japan (Detail)
$ in Millions, ¥ in Billions
 12 Months Ended
Dec. 31, 2021
USD ($)
Dec. 31, 2021
JPY (¥)
Dec. 31, 2020
USD ($)
Dec. 31, 2020
JPY (¥)
Dec. 31, 2019
USD ($)
Dec. 31, 2019
JPY (¥)
Insurance [Abstract]            
Profit remittances $ 2,138 ¥ 236.7 $ 1,215 ¥ 129.8 $ 2,070 ¥ 225.2
v3.22.0.1
BENEFIT PLANS - Additional Information (Detail) - USD ($)
shares in Millions, $ in Millions
 3 Months Ended 12 Months Ended
Jan. 01, 2021
Dec. 31, 2020
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Amount of years active employees have left to meet rule of 80 in order to be eligible for postretirement medical benefits           5 years
Amount of years left to meet 15 year service requirement for active employees age 55 or older to be eligible for postretirement medical benefits           5 years
Net periodic (benefit) cost, excluding service cost     $ 25 $ 30 $ 8  
Transition obligation     $ 0      
Percentage of matching contributions by the Company to employee's contributions to 401(k) plan     100.00%      
Non-elective defined contribution percentage of employee compensation     2.00%      
Matching 401(k) plan contributions included in acquisition and operating expenses     $ 20 20 18  
Shares of employer-issued common stock held for plan participants by plan trustee (in millions)     2.2      
Severance Charges, Voluntary Separation Program   $ 43        
Lower Limit            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Health care plan, retirement age and years of service combined years for eligibility (rule of 80)           80 years
Health care plan, retirement age for eligibility, (in years)           55 years
Health care plan, number of years of service for eligibility           15 years
Upper Limit            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Percentage of matching contributions by the Company to employee's contributions to 401(k) plan 4.00%   4.00%      
Associate Stock Bonus Plan            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Deferred policy acquisition costs, amount attributable to stock bonus plan     $ 15 24 31  
Foreign Plan | Pension Plan            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Defined benefit plan, expected contributions to the plan in the following year     $ 36      
Japan            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
AA corporate bonds average duration     20 years      
Japan | Pension Plan            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Defined benefit plan, plan assets, amount   416 $ 415 416 344  
Employer contributions     $ 44 41    
U.S.            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
AA corporate bonds average duration     17 years      
U.S. | Pension Plan            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Defined benefit plan, expected contributions to the plan in the following year     $ 0      
Defined benefit plan, plan assets, amount   824 885 824 $ 644  
Employer contributions     8 107    
U.S. | Pension Plans Defined Benefit Excluding Executive and Director Plans            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Employer contributions     0      
Level 1 | U.S. | Pension Plan | Cash and cash equivalents            
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]            
Defined benefit plan, plan assets, amount   $ 169 $ 2 $ 169    
v3.22.0.1
BENEFIT PLANS - Reconciliation of Funded Status of Basic Employee Defined-Benefit Pension Plans (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Other Postretirement Benefit Plans, Defined Benefit      
Projected benefit obligation:      
Benefit obligation, beginning of year $ 42 $ 39  
Service cost 0 0 $ 0
Interest cost 1 1 1
Actuarial (gain) loss (2) 6  
Benefits and expenses paid (5) (4)  
Effect of foreign exchange rate changes 0 0  
Benefit obligation, end of year 36 42 39
Plan assets:      
Fair value of plan assets, beginning of year 0 0  
Actual return on plan assets 0 0  
Employer contributions 5 4  
Benefits and expenses paid (5) (4)  
Effect of foreign exchange rate changes 0 0  
Fair value of plan assets, end of year 0 0 0
Funded status of the plans [1] (36) (42)  
Amounts recognized in accumulated other comprehensive income:      
Net actuarial (gain) loss 10 15  
Prior service (credit) cost 0 0  
Total included in accumulated other comprehensive income 10 15  
Japan | Pension Plan      
Projected benefit obligation:      
Benefit obligation, beginning of year 473 436  
Service cost 23 24 22
Interest cost 6 5 7
Actuarial (gain) loss (9) (6)  
Benefits and expenses paid (15) (12)  
Effect of foreign exchange rate changes (46) 26  
Benefit obligation, end of year 432 473 436
Plan assets:      
Fair value of plan assets, beginning of year 416 344  
Actual return on plan assets 14 21  
Employer contributions 44 41  
Benefits and expenses paid (15) (12)  
Effect of foreign exchange rate changes (44) 22  
Fair value of plan assets, end of year 415 416 344
Funded status of the plans [1] (17) (57)  
Amounts recognized in accumulated other comprehensive income:      
Net actuarial (gain) loss 50 74  
Prior service (credit) cost 0 (1)  
Total included in accumulated other comprehensive income 50 73  
Accumulated benefit obligation 346 425  
U.S. | Pension Plan      
Projected benefit obligation:      
Benefit obligation, beginning of year 1,204 1,058  
Service cost 28 29 23
Interest cost 32 34 20
Actuarial (gain) loss (50) 106  
Benefits and expenses paid (28) (23)  
Effect of foreign exchange rate changes 0 0  
Benefit obligation, end of year 1,186 1,204 1,058
Plan assets:      
Fair value of plan assets, beginning of year 824 644  
Actual return on plan assets 81 96  
Employer contributions 8 107  
Benefits and expenses paid (28) (23)  
Effect of foreign exchange rate changes 0 0  
Fair value of plan assets, end of year 885 824 $ 644
Funded status of the plans [1] (301) (380)  
Amounts recognized in accumulated other comprehensive income:      
Net actuarial (gain) loss 158 278  
Prior service (credit) cost (2) (2)  
Total included in accumulated other comprehensive income 156 276  
Accumulated benefit obligation $ 1,010 $ 1,017  
[1] Recognized in other liabilities in the consolidated balance sheets
v3.22.0.1
BENEFIT PLANS - Information for Pension Plans with an Accumulated Benefit Obligation in Excess of Plan Assets (Details) - Pension Plan - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Japan    
Defined Benefit Plan Disclosure [Line Items]    
Accumulated benefit obligation $ 346 $ 425
Fair value of plan assets 415 416
U.S.    
Defined Benefit Plan Disclosure [Line Items]    
Accumulated benefit obligation 1,010 1,017
Fair value of plan assets $ 885 $ 824
v3.22.0.1
BENEFIT PLANS - Information for Pension Plans with a Projected Benefit Obligation in Excess of Plan Assets (Details) - Pension Plan - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Japan    
Defined Benefit Plan Disclosure [Line Items]    
Projected benefit obligation [1] $ 432 $ 473
Fair value of plan assets [1] 415 416
Funded status of the plans [2] (17) (57)
U.S.    
Defined Benefit Plan Disclosure [Line Items]    
Projected benefit obligation [3] 1,186 1,204
Fair value of plan assets [3] 885 824
Funded status of the plans [2] $ (301) $ (380)
[1] The net amount of projected benefit obligation and plan assets for the underfunded (including unfunded) Japan pension plan was $17 and $57 at December 31, 2021 and 2020, respectively, and was classified as liabilities on the statement of financial position.
[2] Recognized in other liabilities in the consolidated balance sheets
[3] The net amount of projected benefit obligation and plan assets for the underfunded (including unfunded) U.S. pension plan was $301 and $380 at December 31, 2021 and 2020, respectively, and was classified as liabilities on the statement of financial position.
v3.22.0.1
BENEFIT PLANS - Weighted-Average Actuarial Assumptions (Detail)
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Other Postretirement Benefit Plans, Defined Benefit      
Weighted-average actuarial assumptions:      
Discount rate - net periodic benefit cost 2.68% 3.25% 4.25%
Discount rate - benefit obligations 2.94% 2.68% 3.25%
Health care cost trend rates [1] 5.80% 6.30% 7.50%
Defined benefit plan, ultimate health care cost trend rate 3.70% 3.70% 3.80%
Defined benefit plan number of years that rate reaches ultimate trend rate 52 years 53 years 54 years
Japan | Pension Plan      
Weighted-average actuarial assumptions:      
Discount rate - net periodic benefit cost 0.75% 0.75% 1.25%
Discount rate - benefit obligations 0.94% 0.75% 0.75%
Expected long-term return on plan assets 2.00% 2.00% 2.00%
U.S. | Pension Plan      
Weighted-average actuarial assumptions:      
Discount rate - net periodic benefit cost 2.68% 3.25% 4.25%
Discount rate - benefit obligations 2.94% 2.68% 3.25%
Expected long-term return on plan assets 5.75% 6.00% 6.25%
Rate of compensation increase 4.00% 4.00% 4.00%
[1] For the years 2021, 2020 and 2019, the health care cost trend rates are expected to trend down to 3.7% in 52 years, 3.7% in 53 years, and 3.8% in 54 years, respectively.
v3.22.0.1
BENEFIT PLANS - Net Periodic (Benefit) Cost Included in Acquisition and Operating Expenses (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Other Postretirement Benefit Plans, Defined Benefit      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Service cost $ 0 $ 0 $ 0
Interest cost 1 1 1
Expected return on plan assets 0 0 0
Amortization of net actuarial loss 3 2 1
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) 0 0 0
Net periodic (benefit) cost 4 3 2
Japan | Pension Plan      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Service cost 23 24 22
Interest cost 6 5 7
Expected return on plan assets (8) (7) (6)
Amortization of net actuarial loss 2 4 4
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) 0 (1) 0
Net periodic (benefit) cost 23 25 27
U.S. | Pension Plan      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Service cost 28 29 23
Interest cost 32 34 20
Expected return on plan assets (41) (35) (29)
Amortization of net actuarial loss 30 26 10
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) 0 (2) 0
Net periodic (benefit) cost $ 49 $ 52 $ 24
v3.22.0.1
BENEFIT PLANS - Summary of Amounts Recognized in Other Comprehensive Loss (Income) (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Other Postretirement Benefit Plans, Defined Benefit      
Defined Benefit Plan Disclosure [Line Items]      
Net actuarial loss (gain) $ (2) $ 5 $ 4
Amortization of net actuarial loss (3) (2) (1)
Amortization of prior service cost 0 0 0
Total (5) 3 3
Japan | Pension Plan      
Defined Benefit Plan Disclosure [Line Items]      
Net actuarial loss (gain) (22) (14) 1
Amortization of net actuarial loss (2) (4) (4)
Amortization of prior service cost (1) (1) 0
Total (23) (17) (3)
U.S. | Pension Plan      
Defined Benefit Plan Disclosure [Line Items]      
Net actuarial loss (gain) (90) 45 95
Amortization of net actuarial loss (30) (26) (10)
Amortization of prior service cost 0 (2) 0
Total $ (120) $ 21 $ 85
v3.22.0.1
BENEFIT PLANS - Expected Benefit Payments (Detail)
$ in Millions
Dec. 31, 2021
USD ($)
Other Postretirement Benefit Plans, Defined Benefit  
Schedule of Postemployment Expected Future Benefit Payments [Line Items]  
2022 $ 5
2023 5
2024 5
2025 4
2026 4
2027-2031 9
Japan | Pension Plan  
Schedule of Postemployment Expected Future Benefit Payments [Line Items]  
2022 17
2023 14
2024 16
2025 17
2026 17
2027-2031 88
U.S. | Pension Plan  
Schedule of Postemployment Expected Future Benefit Payments [Line Items]  
2022 32
2023 32
2024 34
2025 35
2026 37
2027-2031 $ 237
v3.22.0.1
BENEFIT PLANS - Asset Allocation Targets (Detail) - Pension Plan
Dec. 31, 2021
Japan  
Defined Benefit Plan Disclosure [Line Items]  
Asset allocation targets 100.00%
U.S.  
Defined Benefit Plan Disclosure [Line Items]  
Asset allocation targets 100.00%
Domestic equity securities | Japan  
Defined Benefit Plan Disclosure [Line Items]  
Asset allocation targets 5.00%
Domestic equity securities | U.S.  
Defined Benefit Plan Disclosure [Line Items]  
Asset allocation targets 40.00%
International equity securities | Japan  
Defined Benefit Plan Disclosure [Line Items]  
Asset allocation targets 21.00%
International equity securities | U.S.  
Defined Benefit Plan Disclosure [Line Items]  
Asset allocation targets 20.00%
Fixed income bond funds | Japan  
Defined Benefit Plan Disclosure [Line Items]  
Asset allocation targets 66.00%
Fixed income bond funds | U.S.  
Defined Benefit Plan Disclosure [Line Items]  
Asset allocation targets 40.00%
Other Investments | Japan  
Defined Benefit Plan Disclosure [Line Items]  
Asset allocation targets 8.00%
Other Investments | U.S.  
Defined Benefit Plan Disclosure [Line Items]  
Asset allocation targets 0.00%
v3.22.0.1
BENEFIT PLANS - Fair Value Hierarchy Levels of Funded Pension Plans' Assets (Detail) - Pension Plan - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Japan      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets $ 415 $ 416 $ 344
U.S.      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets 885 824 $ 644
Japanese equity securities | Japan | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets 21 20  
International equity securities | Japan | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets 86 88  
Japanese bonds | Japan | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets 22 23  
International bonds | Japan | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets 252 249  
Insurance contracts | Japan | Level 2      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets 34 36  
U.S. large cap equity securities | U.S. | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets 297 234  
U.S. mid cap equity securities | U.S. | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets 25 24  
Real estate equity funds | U.S. | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets 0 19  
International equity funds | U.S. | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets 208 136  
Fixed income bond funds | U.S. | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets 346 237  
Aflac Incorporated common stock | U.S. | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets 7 5  
Cash and cash equivalents | U.S. | Level 1      
Defined Benefit Plan Disclosure [Line Items]      
Fair value of pension plan assets $ 2 $ 169  
v3.22.0.1
COMMITMENTS AND CONTINGENT LIABILITIES - Additional Information (Detail)
$ in Millions, ¥ in Billions
 3 Months Ended 12 Months Ended
Mar. 31, 2017
USD ($)
Dec. 31, 2021
JPY (¥)
agreements
Dec. 31, 2021
USD ($)
agreements
Commitments and Contingencies Disclosure [Line Items]      
Number of operating service agreements, technology and consulting | agreements   2 2
Number of operating service agreements, information technology and data services | agreements   2 2
Loss contingency accrual, insurance-related assessment, discount rate 4.25%    
Loss contingency, discounted amount of insurance-related assessment liability $ 62    
Loss contingency, undiscounted amount of insurance-related assessment liability 94    
Loss contingency, insurance related assessment, discounted amount of premium tax offset 48    
Loss contingency, insurance-related assessment, undiscounted amount of premium tax offset 74    
Loss contingency, loss in period $ 14    
Mainframe and server computer operations and support      
Commitments and Contingencies Disclosure [Line Items]      
Outsourcing agreements, remaining term   3 years 3 years
Outsourcing agreements, aggregate remaining cost   ¥ 27.4 $ 238
Technology and consulting company application maintenance and development services      
Commitments and Contingencies Disclosure [Line Items]      
Outsourcing agreements, remaining term   2 years 2 years
Outsourcing agreements, aggregate remaining cost   ¥ 2.6 $ 22
Management consulting and technology services company application maintenance and development services      
Commitments and Contingencies Disclosure [Line Items]      
Outsourcing agreements, remaining term   5 years 5 years
Outsourcing agreements, aggregate remaining cost   ¥ 16.0 $ 140
Information technology and data services company application maintenance and development services first agreement      
Commitments and Contingencies Disclosure [Line Items]      
Outsourcing agreements, remaining term   1 year 1 year
Outsourcing agreements, aggregate remaining cost   ¥ 0.6 $ 5
Information technology and data services company application maintenance and development services second agreement      
Commitments and Contingencies Disclosure [Line Items]      
Outsourcing agreements, remaining term   4 years 4 years
Outsourcing agreements, aggregate remaining cost   ¥ 10.7 $ 93
Enterprise software licensing agreement      
Commitments and Contingencies Disclosure [Line Items]      
Outsourcing agreements, remaining term   2 years 2 years
Outsourcing agreements, aggregate remaining cost   ¥ 2.2 $ 19
v3.22.0.1
Schedule II - Aflac Incorporated (Parent Only) - Condensed Statement of Earnings (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Condensed Income Statements, [Line Items]      
Net investment income $ 3,818 $ 3,638 $ 3,578
Net investment gains (losses) 468 (270) (135)
Total revenues 22,106 22,147 22,307
Interest expense 238 242 228
Total acquisition and operating expenses 6,208 6,192 5,920
Income tax expense (benefit) 997 (619) 1,141
Net earnings 4,325 4,778 3,304
Parent Company      
Condensed Income Statements, [Line Items]      
Management and service fees from subsidiaries [1] 130 131 151
Net investment income (93) 62 77
Interest from subsidiaries [1] 2 3 4
Net investment gains (losses) 206 399 98
Total revenues 245 595 330
Interest expense 222 221 200
Other operating expenses [2] 300 277 221
Total acquisition and operating expenses 522 498 421
Earnings before income taxes and equity in earnings of subsidiaries (277) 97 (91)
Income tax expense (benefit) (144) (15) (22)
Earnings before equity in earnings of subsidiaries (133) 112 (69)
Equity in earnings of subsidiaries [1] 4,458 4,666 3,373
Net earnings 4,325 4,778 $ 3,304
3.625% senior notes paid May 2021      
Condensed Income Statements, [Line Items]      
Expense on extinguishment of debt 48    
3.625% senior notes paid May 2021 | Parent Company      
Condensed Income Statements, [Line Items]      
Expense on extinguishment of debt $ 48    
4.00% senior notes paid January 2020      
Condensed Income Statements, [Line Items]      
Expense on extinguishment of debt   15  
4.00% senior notes paid January 2020 | Parent Company      
Condensed Income Statements, [Line Items]      
Expense on extinguishment of debt   $ 15  
[1] Eliminated in consolidation
[2] Includes expense of $48 in 2021 and $15 in 2020 for the early extinguishment of debt
v3.22.0.1
Schedule II - Aflac Incorporated (Parent Only) - Condensed Statements of Comprehensive Income (Loss) (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Condensed Financial Statements, Captions [Line Items]      
Net earnings $ 4,325 $ 4,778 $ 3,304
Other comprehensive income (loss) before income taxes:      
Unrealized foreign currency translation gains (losses) during period (889) 510 252
Unrealized gains (losses) on derivatives during period 5 (1) (12)
Pension liability adjustment during period 148 (7) (85)
Total other comprehensive income (loss) before income taxes (1,696) 1,722 6,007
Income tax expense (benefit) related to items of other comprehensive income (loss) (155) 251 1,543
Other comprehensive income (loss), net of tax (1,541) 1,471 4,464
Total comprehensive income (loss) 2,784 6,249 7,768
Parent Company      
Condensed Financial Statements, Captions [Line Items]      
Net earnings 4,325 4,778 3,304
Other comprehensive income (loss) before income taxes:      
Unrealized foreign currency translation gains (losses) during period (889) 510 252
Unrealized gains (losses) on fixed maturity securities during period (960) 1,220 5,852
Unrealized gains (losses) on derivatives during period 5 (1) (12)
Pension liability adjustment during period 148 (7) (85)
Total other comprehensive income (loss) before income taxes (1,696) 1,722 6,007
Income tax expense (benefit) related to items of other comprehensive income (loss) (155) 251 1,543
Other comprehensive income (loss), net of tax (1,541) 1,471 4,464
Total comprehensive income (loss) $ 2,784 $ 6,249 $ 7,768
v3.22.0.1
Schedule II - Aflac Incorporated (Parent Only) - Condensed Balance Sheet (Detail 1) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Investments and cash:        
Available for sale, fixed maturity securities $ 98,696 $ 105,882    
Other investments 3,842 2,429    
Cash and cash equivalents 5,051 5,141    
Total investments and cash 142,978 149,753    
Other assets 3,071 2,715    
Assets 157,542 165,086    
Liabilities:        
Notes payable 7,839 7,745    
Other Liabilities 4,760 3,612    
Total liabilities 124,289 131,527    
Shareholders' equity:        
Common stock of $.10 par value. In thousands: authorized 1,900,000 shares in 2021 and 2020; issued 1,352,739 shares in 2021 and 1,351,018 shares in 2020 135 135    
Additional paid-in capital 2,529 2,410    
Retained earnings 41,381 37,984    
Accumulated other comprehensive income (loss):        
Unrealized foreign currency translation gains (losses) (2,013) (1,109)    
Unrealized gains (losses) on fixed maturity securities 9,602 10,361    
Unrealized gains (losses) on derivatives (30) (34)    
Pension liability adjustment (166) (284)    
Treasury stock, at average cost (18,185) (15,904)    
Total shareholders' equity 33,253 33,559 $ 28,959 $ 23,462
Total liabilities and shareholders' equity 157,542 165,086    
Parent Company        
Investments and cash:        
Available for sale, fixed maturity securities 1,828 1,876    
Investments in subsidiaries [1] 35,905 36,217    
Other investments 1,413 902    
Cash and cash equivalents 2,097 2,126 $ 2,508 $ 1,767
Total investments and cash 41,243 41,121    
Due from subsidiaries [1] 248 253    
Income taxes receivable 0 203    
Other assets 640 368    
Assets 42,131 41,945    
Liabilities:        
Employee benefit plans 336 340    
Notes payable 7,579 7,456    
Other Liabilities 963 590    
Total liabilities 8,878 8,386    
Shareholders' equity:        
Common stock of $.10 par value. In thousands: authorized 1,900,000 shares in 2021 and 2020; issued 1,352,739 shares in 2021 and 1,351,018 shares in 2020 135 135    
Additional paid-in capital 2,529 2,410    
Retained earnings 41,381 37,984    
Accumulated other comprehensive income (loss):        
Unrealized foreign currency translation gains (losses) (2,013) (1,109)    
Unrealized gains (losses) on fixed maturity securities 9,602 10,361    
Unrealized gains (losses) on derivatives (30) (34)    
Pension liability adjustment (166) (284)    
Treasury stock, at average cost (18,185) (15,904)    
Total shareholders' equity 33,253 33,559    
Total liabilities and shareholders' equity $ 42,131 $ 41,945    
[1] Eliminated in consolidation
v3.22.0.1
Schedule II - Aflac Incorporated (Parent Only) - Condensed Balance Sheet (Detail 2) - USD ($)
$ / shares in Units, shares in Thousands, $ in Millions
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Condensed Financial Statements, Captions [Line Items]        
Available for sale, fixed maturity securities, amortized cost $ 85,369 $ 91,630    
Common stock, par value (in dollars per share) $ 0.10 $ 0.10    
Common stock, shares authorized (in shares) 1,900,000 1,900,000    
Common stock, shares issued (in shares) 1,352,739 1,351,018 1,349,309 1,347,540
Parent Company        
Condensed Financial Statements, Captions [Line Items]        
Available for sale, fixed maturity securities, amortized cost $ 1,608 $ 1,782    
Common stock, par value (in dollars per share) $ 0.10 $ 0.10    
Common stock, shares authorized (in shares) 1,900,000 1,900,000    
Common stock, shares issued (in shares) 1,352,739 1,351,018    
v3.22.0.1
Schedule II - Aflac Incorporated (Parent Only) - Condensed Statements of Cash Flows (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Cash flows from operating activities:      
Net earnings $ 4,325 $ 4,778 $ 3,304
Adjustments to reconcile net earnings to net cash provided from operating activities:      
Other, net (79) 182 358
Net cash provided (used) by operating activities 5,051 5,958 5,455
Cash flows from investing activities:      
Fixed maturity securities purchased (5,813) (4,772) (6,934)
Other investments sold (purchased) (1,066) (860) (653)
Settlement of derivatives 199 18 (9)
Other, net 41 (265) (123)
Net cash provided (used) by investing activities (2,378) (4,619) (3,171)
Cash flows from financing activities:      
Purchases of treasury stock (2,301) (1,537) (1,627)
Proceeds from borrowings 1,153 1,545 615
Principal payments under debt obligations (700) (350) 0
Dividends paid to shareholders (855) (769) (771)
Treasury stock reissued 26 34 49
Proceeds from exercise of stock options 26 18 40
Other, net (26) (27) 22
Net cash provided (used) by financing activities (2,739) (1,115) (1,713)
Net change in cash and cash equivalents (90) 245 559
Cash and cash equivalents, beginning of period 5,141    
Cash and cash equivalents, end of period 5,051 5,141  
Parent Company      
Cash flows from operating activities:      
Net earnings 4,325 4,778 3,304
Adjustments to reconcile net earnings to net cash provided from operating activities:      
Equity in earnings of subsidiaries [1] (4,458) (4,666) (3,373)
Cash dividends received from subsidiaries 2,791 2,060 3,466
Other, net 408 (331) (203)
Net cash provided (used) by operating activities 3,066 1,841 3,194
Cash flows from investing activities:      
Fixed maturity securities sold 483 438 340
Fixed maturity securities purchased (489) (484) (639)
Other investments sold (purchased) (421) (711) (16)
Settlement of derivatives 135 4 22
Additional capitalization of subsidiaries [1] (161) (291) (214)
Other, net 1 2 87
Net cash provided (used) by investing activities (452) (1,042) (420)
Cash flows from financing activities:      
Purchases of treasury stock (2,301) (1,537) (1,627)
Proceeds from borrowings 1,153 1,545 347
Principal payments under debt obligations (700) (350) 0
Dividends paid to shareholders (855) (769) (771)
Treasury stock reissued 26 34 49
Proceeds from exercise of stock options 17 12 29
Net change in amount due to/from subsidiary [1] 43 (89) (58)
Other, net (26) (27) (2)
Net cash provided (used) by financing activities (2,643) (1,181) (2,033)
Net change in cash and cash equivalents (29) (382) 741
Cash and cash equivalents, beginning of period 2,126 2,508 1,767
Cash and cash equivalents, end of period $ 2,097 $ 2,126 $ 2,508
[1] Eliminated in consolidation
v3.22.0.1
Schedule II - Aflac Incorporated (Parent Only) - Summary of Notes Payable (Detail 1) - USD ($)
$ in Millions
Dec. 31, 2021
May 31, 2021
Apr. 30, 2021
Mar. 31, 2021
Dec. 31, 2020
Apr. 30, 2020
Oct. 31, 2018
Dec. 31, 2017
Oct. 31, 2017
Sep. 30, 2017
Jan. 31, 2017
Mar. 31, 2016
Nov. 30, 2014
Jun. 30, 2013
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 7,839       $ 7,745                  
3.625% senior notes paid May 2021                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 3.625% 3.625%     3.625%                 3.625%
3.625% senior notes due November 2024                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 3.625%       3.625%               3.625%  
3.25% senior notes due March 2025                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 3.25%       3.25%             3.25%    
1.125% senior notes due March 2026                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 1.125%     1.125% 1.125%                  
2.875% senior notes due October 2026                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 2.875%       2.875%         2.875%        
3.60% senior notes due April 2030                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 3.60%       3.60% 3.60%                
6.90% senior notes due December 2039                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 6.90%       6.90%     6.90%            
6.45% senior notes due August 2040                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 6.45%       6.45%     6.45%            
4.00% senior noted due October 2046                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 4.00%       4.00%         4.00%        
4.750% senior notes due January 2049                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 4.75%       4.75%   4.75%              
.300% senior notes due September 2025                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 0.30%     0.30%                    
.932% senior notes due January 2027                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 0.932%       0.932%           0.932%      
.500% senior notes due December 2029                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 0.50%       0.50%                  
.550% senior notes due March 2030                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 0.55%     0.55%                    
1.159% senior notes due October 2030                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 1.159%       1.159%   1.159%              
.633% senior notes due April 2031                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 0.633%   0.633%   0.633%                  
.843% senior notes due December 2031                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 0.843%       0.843%                  
.750% senior notes due March 2032                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 0.75%     0.75% 0.75%                  
.844% senior notes due April 2033                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 0.844%   0.844%   0.844%                  
1.488% senior notes due October 2033                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 1.488%       1.488%   1.488%              
.934% senior notes due December 2034                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 0.934%       0.934%                  
.830% senior notes due March 2035                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 0.83%     0.83% 0.83%                  
1.039% senior notes due April 2036                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 1.039%   1.039%   1.039%                  
1.750% senior notes due October 2038                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 1.75%       1.75%   1.75%              
1.122% senior notes due December 2039                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 1.122%       1.122%                  
1.264% senior notes due April 2041                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 1.264%   1.264%   1.264%                  
2.108% subordinated notes due October 2047                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 2.108%       2.108%       2.108%          
1.560% senior notes due April 2051                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 1.56%   1.56%   1.56%                  
Yen-denominated loan variable interest rate due September 2026                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 0.41%       0.43%                  
Yen-denominated loan variable interest rate due September 2029                            
Condensed Financial Statements, Captions [Line Items]                            
Debt Instrument, Interest Rate, Stated Percentage 0.56%       0.58%                  
Parent Company                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 7,579       $ 7,456                  
Parent Company | 3.625% senior notes paid May 2021                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 0       $ 698                  
Debt Instrument, Interest Rate, Stated Percentage 3.625% 3.625%     3.625%                  
Parent Company | 3.625% senior notes due November 2024                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 748       $ 747                  
Debt Instrument, Interest Rate, Stated Percentage 3.625%       3.625%                  
Parent Company | 3.25% senior notes due March 2025                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 448       $ 448                  
Debt Instrument, Interest Rate, Stated Percentage 3.25%       3.25%                  
Parent Company | 1.125% senior notes due March 2026                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 397       $ 0                  
Debt Instrument, Interest Rate, Stated Percentage 1.125%     1.125% 1.125%                  
Parent Company | 2.875% senior notes due October 2026                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 298       $ 298                  
Debt Instrument, Interest Rate, Stated Percentage 2.875%       2.875%                  
Parent Company | 3.60% senior notes due April 2030                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 991       $ 990                  
Debt Instrument, Interest Rate, Stated Percentage 3.60%       3.60%                  
Parent Company | 6.90% senior notes due December 2039                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 221       $ 221                  
Debt Instrument, Interest Rate, Stated Percentage 6.90%       6.90%                  
Parent Company | 6.45% senior notes due August 2040                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 255       $ 254                  
Debt Instrument, Interest Rate, Stated Percentage 6.45%       6.45%                  
Parent Company | 4.00% senior noted due October 2046                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 394       $ 394                  
Debt Instrument, Interest Rate, Stated Percentage 4.00%       4.00%                  
Parent Company | 4.750% senior notes due January 2049                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 541       $ 541                  
Debt Instrument, Interest Rate, Stated Percentage 4.75%       4.75%                  
Parent Company | .300% senior notes due September 2025                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 107       $ 119                  
Debt Instrument, Interest Rate, Stated Percentage 0.30%       0.30%                  
Parent Company | .932% senior notes due January 2027                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 520       $ 578                  
Debt Instrument, Interest Rate, Stated Percentage 0.932%       0.932%                  
Parent Company | .500% senior notes due December 2029                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 109       $ 121                  
Debt Instrument, Interest Rate, Stated Percentage 0.50%       0.50%                  
Parent Company | .550% senior notes due March 2030                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 115       $ 127                  
Debt Instrument, Interest Rate, Stated Percentage 0.55%       0.55%                  
Parent Company | 1.159% senior notes due October 2030                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 254       $ 282                  
Debt Instrument, Interest Rate, Stated Percentage 1.159%       1.159%                  
Parent Company | .633% senior notes due April 2031                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 259       $ 0                  
Debt Instrument, Interest Rate, Stated Percentage 0.633%   0.633%   0.633%                  
Parent Company | .843% senior notes due December 2031                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 81       $ 90                  
Debt Instrument, Interest Rate, Stated Percentage 0.843%       0.843%                  
Parent Company | .750% senior notes due March 2032                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 179       $ 198                  
Debt Instrument, Interest Rate, Stated Percentage 0.75%       0.75%                  
Parent Company | .844% senior notes due April 2033                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 104       $ 0                  
Debt Instrument, Interest Rate, Stated Percentage 0.844%   0.844%   0.844%                  
Parent Company | 1.488% senior notes due October 2033                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 131       $ 146                  
Debt Instrument, Interest Rate, Stated Percentage 1.488%       1.488%                  
Parent Company | .934% senior notes due December 2034                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 85       $ 94                  
Debt Instrument, Interest Rate, Stated Percentage 0.934%       0.934%                  
Parent Company | .830% senior notes due March 2035                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 91       $ 101                  
Debt Instrument, Interest Rate, Stated Percentage 0.83%       0.83%                  
Parent Company | 1.039% senior notes due April 2036                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 86       $ 0                  
Debt Instrument, Interest Rate, Stated Percentage 1.039%   1.039%   1.039%                  
Parent Company | 1.750% senior notes due October 2038                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 77       $ 85                  
Debt Instrument, Interest Rate, Stated Percentage 1.75%       1.75%                  
Parent Company | 1.122% senior notes due December 2039                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 54       $ 61                  
Debt Instrument, Interest Rate, Stated Percentage 1.122%       1.122%                  
Parent Company | 1.264% senior notes due April 2041                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 86       $ 0                  
Debt Instrument, Interest Rate, Stated Percentage 1.264%   1.264%   1.264%                  
Parent Company | 2.108% subordinated notes due October 2047                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 517       $ 575                  
Debt Instrument, Interest Rate, Stated Percentage 2.108%       2.108%                  
Parent Company | 1.560% senior notes due April 2051                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 172       $ 0                  
Debt Instrument, Interest Rate, Stated Percentage 1.56%   1.56%   1.56%                  
Parent Company | Yen-denominated loan variable interest rate due September 2026                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 43       $ 48                  
Debt Instrument, Interest Rate, Stated Percentage 0.41%       0.43%                  
Parent Company | Yen-denominated loan variable interest rate due September 2029                            
Condensed Financial Statements, Captions [Line Items]                            
Notes payable $ 216       $ 240                  
Debt Instrument, Interest Rate, Stated Percentage 0.56%       0.58%                  
v3.22.0.1
Schedule II - Aflac Incorporated (Parent Only) - Summary of Notes Payable (Detail 2)
¥ in Millions, $ in Millions
Dec. 31, 2021
JPY (¥)
May 31, 2021
Apr. 30, 2021
JPY (¥)
Mar. 31, 2021
JPY (¥)
Mar. 31, 2021
USD ($)
Dec. 31, 2020
JPY (¥)
Sep. 30, 2020
JPY (¥)
Apr. 30, 2020
USD ($)
Oct. 31, 2018
JPY (¥)
Oct. 31, 2018
USD ($)
Dec. 31, 2017
Oct. 31, 2017
JPY (¥)
Sep. 30, 2017
USD ($)
Jan. 31, 2017
JPY (¥)
Mar. 31, 2016
USD ($)
Nov. 30, 2014
USD ($)
Jun. 30, 2013
USD ($)
Aug. 31, 2010
USD ($)
Dec. 31, 2009
USD ($)
3.625% senior notes paid May 2021                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 3.625% 3.625%       3.625%                     3.625%    
Debt instrument, principal amount | $                                 $ 700    
3.625% senior notes due November 2024                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 3.625%         3.625%                   3.625%      
Debt instrument, principal amount | $                               $ 750      
3.25% senior notes due March 2025                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 3.25%         3.25%                 3.25%        
Debt instrument, principal amount | $                             $ 450        
1.125% senior notes due March 2026                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.125%     1.125% 1.125% 1.125%                          
Debt instrument, principal amount | $         $ 400                            
2.875% senior notes due October 2026                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 2.875%         2.875%             2.875%            
Debt instrument, principal amount | $                         $ 300            
3.60% senior notes due April 2030                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 3.60%         3.60%   3.60%                      
Debt instrument, principal amount | $               $ 1,000                      
6.90% senior notes due December 2039                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 6.90%         6.90%         6.90%                
Debt instrument, principal amount | $                                     $ 400
6.45% senior notes due August 2040                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 6.45%         6.45%         6.45%                
Debt instrument, principal amount | $                                   $ 450  
4.00% senior noted due October 2046                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 4.00%         4.00%             4.00%            
Debt instrument, principal amount | $                         $ 400            
4.750% senior notes due January 2049                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 4.75%         4.75%     4.75% 4.75%                  
Debt instrument, principal amount | $                   $ 550                  
.300% senior notes due September 2025                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.30%     0.30% 0.30%                            
Debt instrument, principal amount ¥ 12,400     ¥ 12,400                              
.932% senior notes due January 2027                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.932%         0.932%               0.932%          
Debt instrument, principal amount ¥ 60,000         ¥ 60,000               ¥ 60,000          
.500% senior notes due December 2029                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.50%         0.50%                          
Debt instrument, principal amount ¥ 12,600         ¥ 12,600                          
.550% senior notes due March 2030                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.55%     0.55% 0.55%                            
Debt instrument, principal amount ¥ 13,300     ¥ 13,300                              
1.159% senior notes due October 2030                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.159%         1.159%     1.159% 1.159%                  
Debt instrument, principal amount ¥ 29,300         ¥ 29,300     ¥ 29,300                    
.633% senior notes due April 2031                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.633%   0.633%     0.633%                          
Debt instrument, principal amount ¥ 30,000   ¥ 30,000     ¥ 30,000                          
.843% senior notes due December 2031                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.843%         0.843%                          
Debt instrument, principal amount ¥ 9,300         ¥ 9,300                          
.750% senior notes due March 2032                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.75%     0.75% 0.75% 0.75%                          
Debt instrument, principal amount ¥ 20,700     ¥ 20,700   ¥ 20,700                          
.844% senior notes due April 2033                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.844%   0.844%     0.844%                          
Debt instrument, principal amount ¥ 12,000   ¥ 12,000     ¥ 12,000                          
1.488% senior notes due October 2033                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.488%         1.488%     1.488% 1.488%                  
Debt instrument, principal amount ¥ 15,200         ¥ 15,200     ¥ 15,200                    
.934% senior notes due December 2034                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.934%         0.934%                          
Debt instrument, principal amount ¥ 9,800         ¥ 9,800                          
.830% senior notes due March 2035                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.83%     0.83% 0.83% 0.83%                          
Debt instrument, principal amount ¥ 10,600     ¥ 10,600   ¥ 10,600                          
1.039% senior notes due April 2036                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.039%   1.039%     1.039%                          
Debt instrument, principal amount ¥ 10,000   ¥ 10,000     ¥ 10,000                          
1.750% senior notes due October 2038                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.75%         1.75%     1.75% 1.75%                  
Debt instrument, principal amount ¥ 8,900         ¥ 8,900     ¥ 8,900                    
1.122% senior notes due December 2039                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.122%         1.122%                          
Debt instrument, principal amount ¥ 6,300         ¥ 6,300                          
1.264% senior notes due April 2041                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.264%   1.264%     1.264%                          
Debt instrument, principal amount ¥ 10,000   ¥ 10,000     ¥ 10,000                          
2.108% subordinated notes due October 2047                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 2.108%         2.108%           2.108%              
Debt instrument, principal amount ¥ 60,000         ¥ 60,000           ¥ 60,000              
1.560% senior notes due April 2051                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.56%   1.56%     1.56%                          
Debt instrument, principal amount ¥ 20,000   ¥ 20,000                                
Yen-denominated loan variable interest rate due September 2026                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.41%         0.43%                          
Debt instrument, principal amount ¥ 5,000         ¥ 5,000 ¥ 5,000                        
Yen-denominated loan variable interest rate due September 2029                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.56%         0.58%                          
Debt instrument, principal amount ¥ 25,000         ¥ 25,000 ¥ 25,000                        
Parent Company | 3.625% senior notes paid May 2021                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 3.625% 3.625%       3.625%                          
Parent Company | 3.625% senior notes due November 2024                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 3.625%         3.625%                          
Parent Company | 3.25% senior notes due March 2025                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 3.25%         3.25%                          
Parent Company | 1.125% senior notes due March 2026                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.125%     1.125% 1.125% 1.125%                          
Debt instrument, principal amount | $         $ 400                            
Parent Company | 2.875% senior notes due October 2026                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 2.875%         2.875%                          
Parent Company | 3.60% senior notes due April 2030                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 3.60%         3.60%                          
Parent Company | 6.90% senior notes due December 2039                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 6.90%         6.90%                          
Parent Company | 6.45% senior notes due August 2040                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 6.45%         6.45%                          
Parent Company | 4.00% senior noted due October 2046                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 4.00%         4.00%                          
Parent Company | 4.750% senior notes due January 2049                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 4.75%         4.75%                          
Parent Company | .300% senior notes due September 2025                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.30%         0.30%                          
Debt instrument, principal amount ¥ 12,400         ¥ 12,400                          
Parent Company | .932% senior notes due January 2027                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.932%         0.932%                          
Debt instrument, principal amount ¥ 60,000         ¥ 60,000                          
Parent Company | .500% senior notes due December 2029                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.50%         0.50%                          
Debt instrument, principal amount ¥ 12,600         ¥ 12,600                          
Parent Company | .550% senior notes due March 2030                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.55%         0.55%                          
Debt instrument, principal amount ¥ 13,300         ¥ 13,300                          
Parent Company | 1.159% senior notes due October 2030                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.159%         1.159%                          
Debt instrument, principal amount ¥ 29,300         ¥ 29,300                          
Parent Company | .633% senior notes due April 2031                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.633%   0.633%     0.633%                          
Debt instrument, principal amount ¥ 30,000   ¥ 30,000     ¥ 30,000                          
Parent Company | .843% senior notes due December 2031                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.843%         0.843%                          
Debt instrument, principal amount ¥ 9,300         ¥ 9,300                          
Parent Company | .750% senior notes due March 2032                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.75%         0.75%                          
Debt instrument, principal amount ¥ 20,700         ¥ 20,700                          
Parent Company | .844% senior notes due April 2033                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.844%   0.844%     0.844%                          
Debt instrument, principal amount ¥ 12,000   ¥ 12,000     ¥ 12,000                          
Parent Company | 1.488% senior notes due October 2033                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.488%         1.488%                          
Debt instrument, principal amount ¥ 15,200         ¥ 15,200                          
Parent Company | .934% senior notes due December 2034                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.934%         0.934%                          
Debt instrument, principal amount ¥ 9,800         ¥ 9,800                          
Parent Company | .830% senior notes due March 2035                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.83%         0.83%                          
Debt instrument, principal amount ¥ 10,600         ¥ 10,600                          
Parent Company | 1.039% senior notes due April 2036                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.039%   1.039%     1.039%                          
Debt instrument, principal amount ¥ 10,000   ¥ 10,000     ¥ 10,000                          
Parent Company | 1.750% senior notes due October 2038                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.75%         1.75%                          
Debt instrument, principal amount ¥ 8,900         ¥ 8,900                          
Parent Company | 1.122% senior notes due December 2039                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.122%         1.122%                          
Debt instrument, principal amount ¥ 6,300         ¥ 6,300                          
Parent Company | 1.264% senior notes due April 2041                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.264%   1.264%     1.264%                          
Debt instrument, principal amount ¥ 10,000   ¥ 10,000     ¥ 10,000                          
Parent Company | 2.108% subordinated notes due October 2047                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 2.108%         2.108%                          
Debt instrument, principal amount ¥ 60,000         ¥ 60,000                          
Parent Company | 1.560% senior notes due April 2051                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 1.56%   1.56%     1.56%                          
Debt instrument, principal amount ¥ 20,000   ¥ 20,000     ¥ 20,000                          
Parent Company | Yen-denominated loan variable interest rate due September 2026                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.41%         0.43%                          
Debt instrument, principal amount ¥ 5,000         ¥ 5,000                          
Parent Company | Yen-denominated loan variable interest rate due September 2029                                      
Condensed Financial Statements, Captions [Line Items]                                      
Debt instrument, interest rate 0.56%         0.58%                          
Debt instrument, principal amount ¥ 25,000         ¥ 25,000                          
v3.22.0.1
Schedule II - Aflac Incorporated (Parent Only) - Additional Information (Detail)
$ in Millions, ¥ in Billions
 1 Months Ended
May 31, 2021
USD ($)
Mar. 31, 2021
JPY (¥)
series
Jun. 30, 2013
USD ($)
Dec. 31, 2021
JPY (¥)
Apr. 30, 2021
JPY (¥)
series
Mar. 31, 2021
USD ($)
series
Dec. 31, 2020
JPY (¥)
series
Oct. 31, 2018
JPY (¥)
series
Sep. 30, 2017
USD ($)
series
Condensed Financial Statements, Captions [Line Items]                  
Number of series of senior notes issued through a U.S. public debt offering (in series) | series   4     5 4 4 3 2
Senior notes                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount   ¥ 57.0     ¥ 82.0   ¥ 38.0 ¥ 53.4 $ 700
.633% senior notes due April 2031                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount       ¥ 30.0 ¥ 30.0   ¥ 30.0    
Debt instrument, interest rate       0.633% 0.633%   0.633%    
.844% senior notes due April 2033                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount       ¥ 12.0 ¥ 12.0   ¥ 12.0    
Debt instrument, interest rate       0.844% 0.844%   0.844%    
1.039% senior notes due April 2036                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount       ¥ 10.0 ¥ 10.0   ¥ 10.0    
Debt instrument, interest rate       1.039% 1.039%   1.039%    
1.264% senior notes due April 2041                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount       ¥ 10.0 ¥ 10.0   ¥ 10.0    
Debt instrument, interest rate       1.264% 1.264%   1.264%    
1.560% senior notes due April 2051                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount       ¥ 20.0 ¥ 20.0        
Debt instrument, interest rate       1.56% 1.56%   1.56%    
3.625% senior notes paid May 2021                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount | $     $ 700            
Debt instrument, interest rate 3.625%   3.625% 3.625%     3.625%    
Repayments of debt | $ $ 700                
Debt instrument, redemption, description     These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the treasury rate plus 20 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.            
1.125% senior notes due March 2026                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount | $           $ 400      
Debt instrument, interest rate   1.125%   1.125%   1.125% 1.125%    
Debt instrument, redemption, description   These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 10 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.              
Parent Company                  
Condensed Financial Statements, Captions [Line Items]                  
Number of series of senior notes issued through a U.S. public debt offering (in series) | series         5        
Parent Company | Senior notes                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount         ¥ 82.0        
Parent Company | .633% senior notes due April 2031                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount       ¥ 30.0 ¥ 30.0   ¥ 30.0    
Debt instrument, interest rate       0.633% 0.633%   0.633%    
Parent Company | .844% senior notes due April 2033                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount       ¥ 12.0 ¥ 12.0   ¥ 12.0    
Debt instrument, interest rate       0.844% 0.844%   0.844%    
Parent Company | 1.039% senior notes due April 2036                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount       ¥ 10.0 ¥ 10.0   ¥ 10.0    
Debt instrument, interest rate       1.039% 1.039%   1.039%    
Parent Company | 1.264% senior notes due April 2041                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount       ¥ 10.0 ¥ 10.0   ¥ 10.0    
Debt instrument, interest rate       1.264% 1.264%   1.264%    
Parent Company | 1.560% senior notes due April 2051                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount       ¥ 20.0 ¥ 20.0   ¥ 20.0    
Debt instrument, interest rate       1.56% 1.56%   1.56%    
Parent Company | 3.625% senior notes paid May 2021                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, interest rate 3.625%     3.625%     3.625%    
Repayments of debt | $ $ 700                
Parent Company | 1.125% senior notes due March 2026                  
Condensed Financial Statements, Captions [Line Items]                  
Debt instrument, principal amount | $           $ 400      
Debt instrument, interest rate   1.125%   1.125%   1.125% 1.125%    
Debt instrument, redemption, description   These notes are redeemable at the Parent Company's option in whole at any time or in part from time to time at a redemption price equal to the greater of: (i) the aggregate principal amount of the notes to be redeemed or (ii) the amount equal to the sum of the present values of the remaining scheduled payments for principal of and interest on the notes to be redeemed, not including any portion of the payments of interest accrued as of such redemption date, discounted to such redemption date on a semiannual basis at the yield to maturity for a U.S. Treasury security with a maturity comparable to the remaining term of the notes, plus 10 basis points, plus in each case, accrued and unpaid interest on the principal amount of the notes to be redeemed to, but excluding, such redemption date.              
v3.22.0.1
Schedule II - Aflac Incorporated - Aggregate Contractual Maturities of Notes Payable (Detail)
$ in Millions
Dec. 31, 2021
USD ($)
Condensed Financial Statements, Captions [Line Items]  
2022 $ 0
2023 0
2024 750
2025 558
2026 743
Thereafter 5,847
Total 7,898
Parent Company  
Condensed Financial Statements, Captions [Line Items]  
2022 0
2023 0
2024 750
2025 558
2026 743
Thereafter 5,586
Total $ 7,637
v3.22.0.1
Schedule II - Aflac Incorporated (Parent Only) - Supplemental Disclosure of Cash Flow Information (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Shareholder dividend reinvestment      
Condensed Cash Flow Statements, Captions [Line Items]      
Treasury stock issued for shareholder dividend reinvestment $ 32 $ 29 $ 30
Parent Company      
Condensed Cash Flow Statements, Captions [Line Items]      
Interest paid 213 209 189
Parent Company | Shareholder dividend reinvestment      
Condensed Cash Flow Statements, Captions [Line Items]      
Treasury stock issued for shareholder dividend reinvestment $ 32 $ 29 $ 30
v3.22.0.1
SCHEDULE III SUPPLEMENTARY INSURANCE INFORMATION - (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]      
Deferred policy acquisition costs $ 9,525 $ 10,441  
Future policy benefits & unpaid policy claims 95,424 102,970  
Unearned premiums 2,576 3,597  
Other policyholders' funds 7,072 7,824  
Net premium income 17,647 18,622 $ 18,780
Net investment income 3,818 3,638 3,578
Benefits and claims, net 10,576 11,796 11,942
Amortization of deferred policy acquisition costs 1,170 1,214 1,282
Other operating expenses 5,038 4,978 4,638
Premiums written 17,137 18,075 18,180
Intercompany eliminations      
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]      
Deferred policy acquisition costs 0 0  
Future policy benefits & unpaid policy claims (733) (821)  
Unearned premiums 0 0  
Other policyholders' funds 0 0  
Aflac Japan      
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]      
Deferred policy acquisition costs 6,233 6,991 6,584
Future policy benefits & unpaid policy claims 84,079 91,829  
Unearned premiums 2,469 3,488  
Other policyholders' funds 7,064 7,811  
Net premium income 11,853 12,670 12,772
Net investment income 3,139 2,856 2,753
Benefits and claims, net 7,963 8,851 8,877
Amortization of deferred policy acquisition costs 653 644 709
Other operating expenses 2,555 2,613 2,465
Premiums written 11,600 12,312 12,367
Aflac U.S.      
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]      
Deferred policy acquisition costs 3,292 3,450 3,544
Future policy benefits & unpaid policy claims 11,798 11,684  
Unearned premiums 111 113  
Other policyholders' funds 8 13  
Net premium income 5,614 5,758 5,808
Net investment income 752 702 720
Benefits and claims, net 2,447 2,765 2,871
Amortization of deferred policy acquisition costs 517 570 573
Other operating expenses 2,048 1,963 1,834
Premiums written 5,537 5,763 5,813
All other      
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]      
Deferred policy acquisition costs 0 0  
Future policy benefits & unpaid policy claims 280 278  
Unearned premiums (4) (4)  
Other policyholders' funds 0 0  
Net premium income 180 194 200
Net investment income (73) 80 105
Benefits and claims, net 166 180 194
Amortization of deferred policy acquisition costs 0 0 0
Other operating expenses 435 402 339
Premiums written $ 0 $ 0 $ 0
v3.22.0.1
SCHEDULE IV REINSURANCE Schedule IV - Reinsurance (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]      
Gross Amount, Life Insurance in Force $ 134,577 $ 148,801 $ 146,585
Ceded to Other Companies, Life Insurance in Force 7,199 7,016 6,592
Assumed from Other Companies, Life Insurance in Force 22,568 20,662 0
Net Amount, Life Insurance in Force $ 149,946 $ 162,447 $ 139,993
Percentage of Amount Assumed to Net, Life Insurance in Force 15.00% 13.00% 0.00%
Gross amount $ 17,857 $ 18,955 $ 19,122
Ceded to Other Companies 504 553 547
Assumed from Other companies 294 220 205
Net Amount $ 17,647 $ 18,622 $ 18,780
Percentage of Amount Assumed to Net 2.00% 1.00% 1.00%
Health insurance      
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]      
Gross amount $ 14,913 $ 15,682 $ 15,657
Ceded to Other Companies 475 526 527
Assumed from Other companies 253 213 205
Net Amount $ 14,691 $ 15,369 $ 15,335
Percentage of Amount Assumed to Net 2.00% 1.00% 1.00%
Life insurance      
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items]      
Gross amount $ 2,944 $ 3,273 $ 3,465
Ceded to Other Companies 29 27 20
Assumed from Other companies 41 7 0
Net Amount $ 2,956 $ 3,253 $ 3,445
Percentage of Amount Assumed to Net 1.00% 0.00% 0.00%