Document and Entity Information Document - shares	9 Months Ended
Document and Entity Information Document - shares	Sep. 30, 2018	Nov. 02, 2018
Document and Entity Information
Entity Registrant Name	CENTURYLINK, INC
Entity Central Index Key	0000018926
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		1,080,659,270
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q3

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
OPERATING REVENUES	$ 5,818	$ 4,034	$ 17,665	$ 12,333
OPERATING EXPENSES
Cost of services and products (exclusive of depreciation and amortization)	2,672	1,927	8,205	5,705
Selling, general and administrative	967	710	3,191	2,404
Depreciation and amortization	1,285	910	3,858	2,739
Total operating expenses	4,924	3,547	15,254	10,848
OPERATING INCOME	894	487	2,411	1,485
OTHER (EXPENSE) INCOME
Interest expense	(557)	(362)	(1,638)	(1,000)
Net loss on early retirement of debt	(33)	0	(34)	(5)
Other income, net	25	14	63	6
Total other expense, net	(565)	(348)	(1,609)	(999)
INCOME BEFORE INCOME TAX EXPENSE	329	139	802	486
Income tax expense	57	47	123	214
NET INCOME	$ 272	$ 92	$ 679	$ 272
BASIC AND DILUTED EARNINGS PER COMMON SHARE
BASIC (in dollars per share)	$ 0.25	$ 0.17	$ 0.64	$ 0.50
DILUTED (in dollars per share)	$ 0.25	$ 0.17	$ 0.63	$ 0.50
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
BASIC (in shares)	1,066,904	541,521	1,065,410	541,113
DILUTED (in shares)	1,072,351	541,963	1,069,726	541,879

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 272	$ 92	$ 679	$ 272
Items related to employee benefit plans:
Change in net actuarial loss, net of $(11), $(15), $(33) and $(57) tax	34	36	102	97
Change in net prior service costs, net of $—, $(1), $(2) and $(3) tax	3	2	7	6
Foreign currency translation adjustment and other, net of $(1), $—, $29 and $— tax	(1)	18	(161)	20
Other comprehensive income (loss)	36	56	(52)	123
COMPREHENSIVE INCOME	$ 308	$ 148	$ 627	$ 395

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Change in net actuarial loss, tax	$ (11)	$ (15)	$ (33)	$ (57)
Change in net prior service costs, tax	0	(1)	(2)	(3)
Foreign currency translation adjustment and other, tax	$ 1	$ 0	$ 29	$ 0

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
CURRENT ASSETS
Cash and cash equivalents	$ 390	$ 551
Restricted cash and securities	3	5
Accounts receivable, less allowance of $153 and $164	2,465	2,557
Assets held for sale	19	140
Other	1,237	941
Total current assets	4,114	4,194
Property, plant and equipment, net of accumulated depreciation of $26,493 and $24,352	26,168	26,852
GOODWILL AND OTHER ASSETS
Goodwill	30,770	30,475
Restricted cash and securities	27	31
Customer relationships, net	9,309	10,876
Other intangibles, net	1,857	1,897
Other, net	1,126	1,286
Total goodwill and other assets	43,089	44,565
TOTAL ASSETS	73,371	75,611
CURRENT LIABILITIES
Current maturities of long-term debt	778	443
Accounts payable	1,387	1,555
Accrued expenses and other liabilities
Salaries and benefits	993	890
Income and other taxes	409	370
Interest	362	363
Other	374	344
Current portion of deferred revenue	983	892
Total current liabilities	5,286	4,857
LONG-TERM DEBT	35,749	37,283
DEFERRED CREDITS AND OTHER LIABILITIES
Deferred income taxes, net	2,502	2,413
Benefit plan obligations, net	4,392	5,178
Other	2,639	2,389
Total deferred credits and other liabilities	9,533	9,980
COMMITMENTS AND CONTINGENCIES (Note 12)
STOCKHOLDERS' EQUITY
Preferred stock—non-redeemable, $25 par value, authorized 2,000 and 2,000 shares, issued and outstanding 7 and 7 shares	0	0
Common stock, $1.00 par value, authorized 1,600,000 and 1,600,000 shares, issued and outstanding 1,080,573 and 1,069,169 shares	1,081	1,069
Additional paid-in capital	23,399	23,314
Accumulated other comprehensive loss	(2,454)	(1,995)
Retained earnings	777	1,103
Total stockholders' equity	22,803	23,491
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 73,371	$ 75,611

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Accounts receivable, allowance	$ 153	$ 164
PP&E, accumulated depreciation	$ 26,493	$ 24,352
Preferred stock-non-redeemable, par value (in dollars per share)	$ 25.00	$ 25.00
Preferred stock-non-redeemable, shares authorized (in shares)	2,000,000	2,000,000
Preferred stock-non-redeemable, shares issued (in shares)	7,000	7,000
Preferred stock-non-redeemable, shares outstanding (in shares)	7,000	7,000
Common stock, par value (in dollars per share)	$ 1.00	$ 1.00
Common stock, shares authorized (in shares)	1,600,000,000	1,600,000,000
Common stock, shares issued (in shares)	1,080,573,000	1,069,169,000
Common stock, shares outstanding (in shares)	1,080,573,000	1,069,169,000

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
OPERATING ACTIVITIES
Net income	$ 679	$ 272
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	3,858	2,739
Deferred income taxes	486	(243)
Loss on the sale of data centers and colocation business	0	82
Impairment of assets	46	11
Provision for uncollectible accounts	119	127
Net loss on early retirement of debt	30	5
Share-based compensation	144	64
Changes in current assets and liabilities:
Accounts receivable	(8)	2
Accounts payable	(151)	(93)
Accrued income and other taxes	217	103
Other current assets and liabilities, net	(42)	(221)
Retirement benefits	(639)	(181)
Changes in other noncurrent assets and liabilities, net	324	(54)
Other, net	(27)	87
Net cash provided by operating activities	5,036	2,700
INVESTING ACTIVITIES
Capital expenditures	(2,260)	(2,363)
Proceeds from the sale of data centers and colocation business, less cash sold	0	1,467
Proceeds from sale of property, plant and equipment and other assets	125	51
Other investing, net	(61)	(5)
Net cash used in investing activities	(2,196)	(850)
FINANCING ACTIVITIES
Net proceeds from issuance of long-term debt	130	6,608
Proceeds from financing obligation	0	356
Payments of long-term debt	(1,539)	(1,612)
Net borrowings (payments) on revolving line of credit	185	(370)
Dividends paid	(1,735)	(881)
Other financing, net	(48)	(11)
Net cash (used in) provided by financing activities	(3,007)	4,090
Net (decrease) increase in cash, cash equivalents, restricted cash and securities	(167)	5,940
Cash, cash equivalents, restricted cash and securities at beginning of period	587	224
Cash, cash equivalents, restricted cash and securities at end of period	420	6,164
Supplemental cash flow information:
Income taxes refunded (paid), net	674	(378)
Interest paid (net of capitalized interest of $42 and $61)	$ (1,571)	$ (917)

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Statement of Cash Flows [Abstract]
Capitalized interest	$ 42	$ 61

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Millions	Total	COMMON STOCK	ADDITIONAL PAID-IN CAPITAL	ACCUMULATED OTHER COMPREHENSIVE LOSS	RETAINED EARNINGS
Increase (Decrease) in Stockholders' Equity
Cumulative effect of adoption of ASU \| Accounting Standards Update 2018-02				$ 0	$ 0
Cumulative effect of adoption of ASU \| Accounting Standards Update 2014-09					0
Cumulative effect of adoption of ASU \| Accounting Standards Update 2016-09					3
Balance at beginning of period at Dec. 31, 2016		$ 547	$ 14,970	(2,117)	(1)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock through dividend reinvestment, incentive and benefit plans		3	5
Shares withheld to satisfy tax withholdings			(16)
Share-based compensation and other, net			59
Dividends declared			(648)		(240)
Acquisition of additional minority interest in a subsidiary			0
Other comprehensive income	$ 123			123
Net income	272				272
Balance at end of period at Sep. 30, 2017	$ 12,960	550	14,370	(1,994)	34
Increase (Decrease) in Stockholders' Equity
DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 1.62
Cumulative effect of adoption of ASU \| Accounting Standards Update 2018-02				0	0
Cumulative effect of adoption of ASU \| Accounting Standards Update 2014-09					0
Cumulative effect of adoption of ASU \| Accounting Standards Update 2016-09					0
Balance at beginning of period at Jun. 30, 2017		550	14,637	(2,050)	(51)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock through dividend reinvestment, incentive and benefit plans		0	2
Shares withheld to satisfy tax withholdings			(1)
Share-based compensation and other, net			21
Dividends declared			(289)		(7)
Acquisition of additional minority interest in a subsidiary			0
Other comprehensive income	$ 56			56
Net income	92				92
Balance at end of period at Sep. 30, 2017	$ 12,960	550	14,370	(1,994)	34
Increase (Decrease) in Stockholders' Equity
DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 0.54
Cumulative effect of adoption of ASU	$ (407)
Cumulative effect of adoption of ASU \| Accounting Standards Update 2018-02				(407)	407
Cumulative effect of adoption of ASU \| Accounting Standards Update 2014-09					346
Cumulative effect of adoption of ASU \| Accounting Standards Update 2016-09					0
Balance at beginning of period at Dec. 31, 2017	23,491	1,069	23,314	(1,995)	1,103
Increase (Decrease) in Stockholders' Equity
Issuance of common stock through dividend reinvestment, incentive and benefit plans		12	(2)
Shares withheld to satisfy tax withholdings			(50)
Share-based compensation and other, net			142
Dividends declared			0		(1,758)
Acquisition of additional minority interest in a subsidiary			(5)
Other comprehensive income	(52)			(52)
Net income	679				679
Balance at end of period at Sep. 30, 2018	$ 22,803	1,081	23,399	(2,454)	777
Increase (Decrease) in Stockholders' Equity
DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 1.62
Cumulative effect of adoption of ASU \| Accounting Standards Update 2018-02				0	0
Cumulative effect of adoption of ASU \| Accounting Standards Update 2014-09					49
Cumulative effect of adoption of ASU \| Accounting Standards Update 2016-09					0
Balance at beginning of period at Jun. 30, 2018		1,079	23,360	(2,490)	1,040
Increase (Decrease) in Stockholders' Equity
Issuance of common stock through dividend reinvestment, incentive and benefit plans		2	7
Shares withheld to satisfy tax withholdings			(15)
Share-based compensation and other, net			48
Dividends declared			0		(584)
Acquisition of additional minority interest in a subsidiary			(1)
Other comprehensive income	$ 36			36
Net income	272				272
Balance at end of period at Sep. 30, 2018	$ 22,803	$ 1,081	$ 23,399	$ (2,454)	$ 777
Increase (Decrease) in Stockholders' Equity
DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 0.54

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
RETAINED EARNINGS \| Accounting Standards Update 2014-09
Cumulative net effect of adoption, tax	$ (17)	$ (117)

Background	9 Months Ended
Background	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Background	Background General We are an international facilities-based communications company engaged primarily in providing an integrated array of services to our residential and business customers. Our communications services include local and long-distance voice, virtual private network ("VPN") data network, private line (including special access business data services), Ethernet, network access, information technology, wavelength, broadband, colocation and data center services, managed services, professional and other services provided in connection with selling equipment, network security and various other ancillary services. On November 1, 2017, we acquired Level 3 in a cash and stock transaction. See Note 2—Acquisition of Level 3 for additional information. On May 1, 2017, we sold our data centers and colocation business to a consortium of private equity purchasers for a combination of cash and equity. See Note 3—Sale of Data Centers and Colocation Business for additional information. Basis of Presentation Our consolidated balance sheet as of December 31, 2017, which was derived from our audited consolidated financial statements, and our unaudited interim consolidated financial statements provided herein have been prepared in accordance with the instructions for Form 10-Q. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP") have been condensed or omitted pursuant to rules and regulations of the Securities and Exchange Commission ("SEC"); however, in our opinion, the disclosures made are adequate to make the information presented not misleading. We believe that these consolidated financial statements include all normal recurring adjustments necessary to fairly present the results for the interim periods. The consolidated results of operations and cash flows for the first nine months of the year are not necessarily indicative of the consolidated results of operations and cash flows that might be expected for the entire year. These consolidated financial statements and the accompanying notes should be read in conjunction with the audited consolidated financial statements and the notes thereto included in our annual report on Form 10-K for the year ended December 31, 2017. The accompanying consolidated financial statements include our accounts and the accounts of our subsidiaries in which we have a controlling interest. These subsidiaries include Level 3 on and after November 1, 2017. Intercompany amounts and transactions with our consolidated subsidiaries have been eliminated. In connection with our acquisition of Level 3, we acquired its deconsolidated Venezuela subsidiary, and due to exchange restrictions and other conditions, we have assigned no value to this subsidiary's assets. Additionally, we have excluded this subsidiary from our consolidated financial statements. To simplify the overall presentation of our consolidated financial statements, we report immaterial amounts attributable to noncontrolling interests in certain of our subsidiaries as follows: (i) income attributable to noncontrolling interests in other income (expense), net, (ii) equity attributable to noncontrolling interests in additional paid-in capital and (iii) cash flows attributable to noncontrolling interests in other, net financing activities. We reclassified certain prior period amounts to conform to the current period presentation, including the categorization of our revenues and our segment reporting. See Note 11—Segment Information for additional information. These changes had no impact on total operating revenues, total operating expenses or net income for any period. Income Taxes As of September 30, 2018, we have not completed our accounting for the tax effects of the Tax Cuts and Jobs Act (the "Act") which was signed into law in late December 2017. In order to complete our accounting for the impact of the Act, we continue to obtain, analyze and interpret additional guidance as such guidance becomes available from the U.S. Treasury Department, the Internal Revenue Service (“IRS”), state taxing jurisdictions, the Financial Accounting Standards Board ("FASB"), and other standard-setting and regulatory bodies. Guidance issued by these bodies to date does not allow us to definitively calculate the tax effects of the Act. New guidance or interpretations may materially impact our provision for income taxes in future periods. Additional information that is needed to complete the analysis but is currently unavailable includes, but is not limited to, the amount of earnings of foreign subsidiaries, the final determination of certain net deferred tax assets subject to remeasurement due to purchase accounting adjustments and other matters, and the tax treatment of such provisions of the Act by various state tax authorities. We have provisionally recognized the tax impacts related to the remeasurement of deferred tax assets and liabilities. The ultimate impact may differ from our current provisional estimate due to additional analysis, changes in interpretations and assumptions we have made, additional regulatory guidance that may be issued, and actions we may take as a result of the Act. The change from our current provisional estimates will be reflected in our fourth quarter statement of operations and could be material. We expect to complete the accounting in the fourth quarter of 2018. The Act reduced the U.S. corporate income tax rate from a maximum of 35% to 21% for all C corporations, effective January 1, 2018, introduced further limitations on the deductibility of interest expense, made certain changes to the tax treatment of capital expenditures and various other items, and imposed a one-time repatriation tax on certain earnings of certain foreign subsidiaries. In addition, the Act introduces additional base-broadening measures, including Global Intangible Low-Taxed Income and the Base-Erosion Anti-Abuse Tax. As a result of the reduction in the U.S. corporate income tax rate from 35% to 21%, we provisionally re-measured our net deferred tax liabilities at December 31, 2017 and recognized a tax benefit of approximately $1.1 billion in our consolidated statement of operations for the year ended December 31, 2017. During the first nine months of 2018, we reduced this $1.1 billion tax benefit by $83 million due to changes in certain purchase accounting adjustments related to the Level 3 acquisition, which was reflected in income tax expense over such nine-month period. Additionally, this provisional benefit was further reduced by $208 million by the net deferred tax impact of certain tax accounting method changes filed with our 2017 Federal income tax return that significantly accelerated certain tax deductions into 2017. During the third quarter of 2018, we continued to evaluate and analyze the tax impacts of the Act. While we have not finalized our analysis, we do not expect the provisions of the Act, exclusive of the rate reduction, to materially impact us during the remainder of 2018. However, we cannot provide any assurance that, upon completion of our analysis, the impact will not be material or that there will not be material tax impacts in future years. Accordingly, other than as noted above, we have not made any additional adjustments related to the Act in our consolidated financial statements. As noted above, we accelerated a significant amount of tax deductions into 2017. The accelerated tax deductions resulted in a 2017 net operating loss for tax purposes, a portion of which was carried back to 2016 to generate a cash refund of $392 million, which was received in the third quarter of 2018. Additionally, we received a $314 million refund in the second quarter of 2018 related to 2017 federal income taxes. Based on current circumstances, we do not expect to experience a material near term reduction in the amount of cash income taxes paid by us from the Act due to utilization of net operating loss carryforwards. However, we anticipate that the provisions of the Act may reduce our cash income taxes in future years. Recently Adopted Accounting Pronouncements In the first quarter of 2018, we adopted Accounting Standards Update (“ASU”) 2014-09, “Revenue from Contracts with Customers”, ASU 2018-02, “Income Statement-Reporting Comprehensive Income: Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income” and ASU 2016-16, “Intra-Entity Transfers of Assets Other Than Inventory”. Each of these is described further below. Revenue Recognition In May 2014, the FASB issued ASU 2014-09 which replaces virtually all existing generally accepted accounting principles on revenue recognition and replaces them with a principles-based approach for determining revenue recognition using a new five step model. The core principle of ASU 2014-09 is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 also includes new accounting principles related to the deferral and amortization of contract acquisition and fulfillment costs. We adopted the new revenue recognition standard under the modified retrospective transition method. During the three and nine months ended September 30, 2018, we recorded a cumulative catch-up adjustment that increased our retained earnings by $49 million, net of $17 million of income taxes, and $346 million, net of $117 million of income taxes, respectively. The catch-up adjustment recorded during the three months ended September 30, 2018 resulted from the identification of additional fulfillment costs that should have been considered in our adoption and from correcting certain issues in the accounting system we utilize in calculating revenue under the new revenue recognition standard. Under ASU 2014-09, we are now deferring incremental contract acquisition and fulfillment costs and are recognizing (or amortizing) such costs over either the initial contract (plus anticipated renewal contracts to which the costs relate) or the average customer life. Deferred acquisition and fulfillment costs are amortized based on the transfer of services on a straight-line basis over the average customer life of 30 months for consumer customers and 12 to 60 months for business customers and are included in cost of services and products and selling, general and administrative expenses in our consolidated statement of operations. A portion of these costs are amortized on a portfolio basis using an average expected contract term of 30 months. The amounts of these deferred costs that are anticipated to be amortized in the next twelve months are included in other current assets on our consolidated balance sheets. See Note 5—Revenue Recognition for additional information. Comprehensive Income ASU 2018-02 provides an option to reclassify stranded tax effects within accumulated other comprehensive income to retained earnings in each period in which the effect of the change in the U.S. federal corporate income tax rate in the Act (or portion thereof) is recorded. If an entity elects to reclassify the income tax effects of the Act, the amount of that reclassification shall include the effect of the change in the U.S. federal corporate income tax rate on the gross deferred tax amounts and related valuation allowances, if any, at the date of enactment of the Act related to items remaining in accumulated other comprehensive income. The effect of the change in the U.S. federal corporate income tax rate on gross valuation allowances that were originally charged to income from continuing operations shall not be included. ASU 2018-02 is effective January 1, 2019, but early adoption is permitted and should be applied either in the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the U.S. federal corporate income tax rate in the Act is recognized. We early adopted and applied ASU 2018-02 in the first quarter of 2018. The adoption of ASU 2018-02 resulted in a $407 million increase to retained earnings and in accumulated other comprehensive loss. See Note 14—Accumulated Other Comprehensive Loss for additional information. Income Taxes ASU 2016-16 eliminates the current prohibition on the recognition of the income tax effects on the transfer of assets among our subsidiaries. Prospectively, the income tax effects associated with these asset transfers, except for the transfer of inventory, will be recognized in the period the asset is transferred versus the current deferral and recognition upon either the sale of the asset to a third party or over the remaining useful life of the asset. Our adoption of ASU 2016-16 did not have a material impact to our consolidated financial statements. Recently Issued Accounting Pronouncements Retirement Benefits In August 2018, the FASB issued ASU 2018-14, "Compensation-Retirement Benefits-Defined Benefit Plans-General: Disclosure Framework-Changes to the Disclosure Requirements for Defined Benefit Plans" (“ASU 2018-14“). ASU 2018-14 eliminates requirements for certain disclosures that are not considered cost beneficial, clarifies certain required disclosures and adds additional disclosures under defined benefit pension plans and other postretirement plans. We are required to adopt this guidance beginning January 1, 2021. Early adoption is permitted. The amendments in ASU 2018-14 would need to be applied on a retrospective basis. We are currently evaluating the potential impact of the adoption of this standard on our disclosures. Goodwill Impairment In January 2017, the FASB issued ASU 2017-04, “Simplifying the Test for Goodwill Impairment” (“ASU 2017-04”). ASU 2017-04 simplifies the impairment testing for goodwill by changing the measurement for goodwill impairment. Under current rules, we are required to compute the implied fair value of goodwill to measure the impairment amount if the carrying value of a reporting unit exceeds its fair value. Under ASU 2017-04, the goodwill impairment charge will equal the excess of the reporting unit carrying value above its fair value, limited to the amount of goodwill assigned to the reporting unit. We are required to adopt the provisions of ASU 2017-04 for any goodwill impairment tests, including our required annual test, occurring after January 1, 2020, but have the option to early adopt it for any impairment test that we are required to perform. We have not determined if we will elect to early adopt the provisions of ASU 2017-04. The provisions of ASU 2017-04 would not have affected our last goodwill impairment assessment, but no assurance can be provided that the simplified testing methodology will not affect our goodwill impairment assessment in the future. Financial Instruments In June 2016, the FASB issued ASU 2016-13, "Measurement of Credit Losses on Financial Instruments" ("ASU 2016-13"). The primary impact of ASU 2016-13 for us is a change in the model for the recognition of credit losses related to our financial instruments from an incurred loss model, which recognized credit losses only if it was probable that a loss had been incurred, to an expected loss model, which requires our management team to estimate the total credit losses expected on the portfolio of financial instruments. We are currently reviewing the requirements of the standard and evaluating the impact on our consolidated financial statements. We are required to adopt the provisions of ASU 2016-13 effective January 1, 2020, but could elect to early adopt the provisions as of January 1, 2019. We expect to recognize the impacts of adopting ASU 2016-13 through a cumulative adjustment to retained earnings as of the date of adoption. As of the date of this report, we have not yet determined the date we will adopt ASU 2016-13. Leases In February 2016, the FASB issued ASU 2016-02, “Leases” (“ASU 2016-02”). The core principle of ASU 2016-02 will require lessees to present right-of-use assets and lease liabilities on their balance sheets for operating leases, which under GAAP are currently not required to be reflected on their balance sheets. ASU 2016-02 is effective for annual and interim periods beginning January 1, 2019. Upon adoption of ASU 2016-02, we are required to recognize and measure leases at the beginning of the earliest period presented in our consolidated financial statements using a modified retrospective approach. The modified retrospective transition approach includes a number of optional practical expedients that we may elect to apply. In January 2018, the FASB issued ASU 2018-01, “Leases: Land Easement Practical Expedient for Transition to ASU 2016-02" ("ASU 2018-01"). ASU 2018-01 permits reporting companies to elect to forego reassessments of land easements that exist or expire before the entity’s adoption of ASU 2016-02 and that were not previously accounted for as leases. We plan to adopt ASU 2018-01 at the same time we adopt ASU 2016-02. In July 2018, the FASB issued ASU 2018-11, "Leases: Targeted Improvements" ("ASU 2018-11"). ASU 2018-11 provides entities with an additional (and optional) transition method to adopt the new leases standard. Under this new transition method, an entity initially applies the new leases standard at the adoption date and recognizes a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. We have not yet determined whether we will use ASU 2018-11's newly permitted adoption method. We are in the process of implementing a new lease administration and accounting system. We plan to adopt ASU 2016-02 and ASU 2018-01 effective January 1, 2019. The adoption of ASU 2016-02 will result in our recognition of right of use assets and lease liabilities that we have not previously recorded. Although we believe it is premature as of the date of this report to provide any estimate of the impact of adopting ASU 2016-02, we do expect that it will have a material impact on our consolidated financial statements. Additionally, upon implementing ASU 2016-02, accounting for the failed-sale-leaseback transaction described in Note 3—Sale of Data Centers and Colocation Business will no longer be applicable based on our facts and circumstances, and the real estate assets and corresponding financing obligation described therein will be derecognized from our consolidated financial statements.

Acquisition of Level 3

9 Months Ended

Sep. 30, 2018

Business Combinations [Abstract]

Acquisition of Level 3

On November 1, 2017, CenturyLink acquired Level 3 through successive merger transactions, including a merger of Level 3 with and into a merger subsidiary, which survived such merger as our indirect wholly-owned subsidiary under the name of Level 3 Parent, LLC. Level 3's results of operations have been included in our consolidated results of operations since November 1, 2017.

As of September 30, 2018, our preliminary estimated amount of aggregate consideration was $19.6 billion.

We have recognized the assets and liabilities of Level 3 based on our preliminary estimates of the fair value of the acquired tangible and intangible assets and assumed liabilities of Level 3 as of November 1, 2017, the consummation date of the acquisition, with the excess aggregate consideration recorded as goodwill. The final determination of the allocation of the aggregate consideration we paid in the combination is based on the fair value of such assets and liabilities as of the acquisition date with any excess aggregate consideration to be recorded as goodwill. The estimation of such fair values and the estimation of lives of depreciable tangible assets and amortizable intangible assets require significant judgment. We are reviewing our valuation analysis along with the related allocation to goodwill. We expect to complete our final fair value determinations during the fourth quarter of 2018. We are also reviewing our calculations of the estimates of the fair value of Level 3’s deferred tax assets acquired and liabilities assumed and performing related final controls. Our final fair value determinations may be different than those reflected in our consolidated financial statements at September 30, 2018, however we do not expect that any subsequent modifications to the preliminary purchase price allocation will be material.

The U.S. Department of Justice approved the acquisition subject to conditions of a consent decree on October 2, 2017, which required us to divest (i) certain Level 3 metro network assets in three markets and (ii) 24 strands of dark fiber connecting 30 specified city-pairs across the United States in the form of an indefeasible right of use agreement. During the second quarter of 2018, we sold network assets in Boise, Idaho and Albuquerque, New Mexico that we were required to divest as a condition of the merger. The proceeds from these sales were included in the proceeds from sale of property, plant and equipment in our consolidated statements of cash flows. No gain or loss was recognized with these transactions. All of the metro network assets were classified as assets held for sale on our consolidated balance sheet as of December 31, 2017. The Tucson, Arizona assets continued to be classified as assets held for sale on our consolidated balance sheet as of September 30, 2018. In October 2018, we sold the Tucson, Arizona assets for their net book value.

Based solely on our preliminary estimates through September 30, 2018, the aggregate consideration exceeds the aggregate estimated fair value of the acquired assets and assumed liabilities by $11.2 billion, which we have recognized as goodwill. The goodwill is attributable to strategic benefits, including enhanced financial and operational scale, market diversification and leveraged combined networks that we expect to realize. None of the goodwill associated with this acquisition is deductible for income tax purposes.

As of September 30, 2018, the following is our updated assignment of the preliminary estimated aggregate consideration:



	Adjusted November 1, 2017 Balance as of December 31, 2017			Purchase Price Adjustments ⁽³⁾		Adjusted November 1, 2017 Balance as of September 30, 2018
	(Dollars in millions)
Cash, accounts receivable and other current assets ⁽¹⁾	$	3,317		(25	)	3,292
Property, plant and equipment	9,311			86		9,397
Identifiable intangible assets ⁽²⁾
Customer relationships	8,964			(476	)	8,488
Other	391			(13	)	378
Other noncurrent assets	782			203		985
Current liabilities, excluding current maturities of long-term debt	(1,461		)	(31	)	(1,492	)
Current maturities of long-term debt	(7		)	—		(7	)
Long-term debt	(10,888		)	—		(10,888	)
Deferred revenue and other liabilities	(1,629		)	(102	)	(1,731	)
Goodwill	10,837			353		11,190
Total estimated aggregate consideration	$	19,617		(5	)	19,612

____________________________________________________________________________________________________________


⁽¹⁾	Includes accounts receivable, which had a gross contractual value of $884 million on November 1, 2017 and September 30, 2018.


⁽²⁾	The preliminary estimate of the weighted-average amortization period for the acquired intangible assets is approximately 12.0 years.


⁽³⁾	All purchase price adjustments occurred during the nine months ended September 30, 2018.

On the acquisition date, we assumed Level 3’s contingencies. For more information on our contingencies, see Note 12—Commitments and Contingencies and Other Items.

Acquisition-Related Expenses

We have incurred acquisition-related expenses related to our acquisition of Level 3. The table below summarizes our acquisition-related expenses, which consist of integration-related expenses, including severance and retention compensation expenses, and transaction-related expenses:



	Three Months Ended September 30,			Nine Months Ended September 30,
	2018		2017	2018	2017
	(Dollars in millions)
Transaction-related expenses	$	1	6	2	23
Integration-related expenses	43		28	275	40
Total acquisition-related expenses	$	44	34	277	63

Through September 30, 2018, we had incurred cumulative acquisition-related expenses of $600 million for Level 3. The total amounts of these expenses have been included in our selling, general and administrative expenses beginning in the fourth quarter of 2016.

Level 3 incurred transaction-related expenses of $47 million on the date of acquisition. This amount is not included in our results of operations.

References to Acquired Businesses

In the discussion that follows, we refer to the incremental business activities that we now operate as a result of the Level 3 acquisition as “Legacy Level 3”. References to “Legacy CenturyLink”, when used to compare our consolidated results for the three and nine months ended September 30, 2018 and 2017, mean the business we operated prior to the Level 3 acquisition.

Combined Pro Forma Operating Results (Unaudited)

For the three and nine months ended September 30, 2018, our results of operations included operating revenues (net of intercompany eliminations) attributable to Level 3 of $1.984 billion and $6.071 billion, respectively.

The following unaudited pro forma financial information presents the combined results of CenturyLink as if the Level 3 acquisition had been consummated as of January 1, 2017:



	Three Months Ended September 30, 2017		Nine Months Ended September 30, 2017
	(Dollars in millions, except per share amounts)
Operating revenues	$	6,031	18,316
Net income	194		459
Basic earnings per common share	0.18		0.43
Diluted earnings per common share	0.18		0.43

This pro forma information reflects certain adjustments to previously-reported operating results, consisting primarily but not exclusively of:


•	decreased operating revenues and expenses due to the elimination of transactions among CenturyLink and Level 3 that are now subject to intercompany elimination and the elimination of deferred revenues associated with installation activities that were preliminarily assigned no value at the acquisition date;


•	increased amortization expense related to identifiable intangible assets, net of decreased depreciation expense to reflect the preliminary fair value of property, plant and equipment;

•

increased interest expense resulting from (i) interest on the new debt to finance the combination and amortization of the related debt discount and debt issuance costs, (ii) the elimination of Level 3’s historical amortization of debt discount and debt issuance costs and (iii) a reduction in interest expense due to the accretion of an adjustment to reflect the increased preliminary fair value of the long-term debt of Level 3 recognized on the acquisition date; and


•	the related income tax effects.

The pro forma information is presented for illustrative purposes only and does not necessarily reflect the actual results of operations had the Level 3 acquisition been consummated at January 1, 2017, nor is it necessarily indicative of future operating results. The pro forma information does not reflect:


•	the transaction costs incurred by us and Level 3 during the periods presented above (which are further described above in this note);


•	integration costs incurred by us in future periods; or


•	potential revenue enhancements, cost synergies or other operating efficiencies that could result from the acquisition

As a result of the acquisition of Level 3's net operating losses ("NOL"s), we expect to significantly reduce our federal cash taxes for the next several years.

Sale of Data Centers and Colocation Business

9 Months Ended

Sep. 30, 2018

Discontinued Operations and Disposal Groups [Abstract]

Sale of Data Centers and Colocation Business

On May 1, 2017, we sold our data centers and colocation business to a consortium led by BC Partners, Inc. and Medina Capital in exchange for cash and a minority stake in the limited partnership that owns the consortium's newly-formed global secure infrastructure company, Cyxtera Technologies ("Cyxtera").

We received pre-tax cash proceeds of $1.8 billion, and we have valued our minority stake at $150 million, which was based upon the total equity contribution to the limited partnership on the date made.

In connection with our sale of the data centers and colocation business to Cyxtera, we agreed to lease back from Cyxtera a portion of the data center space to provide data hosting services to our customers. Because we have continuing involvement in the business through our minority stake in Cyxtera's parent, we do not meet the requirements for a sale-leaseback transaction as described in ASC 840-40, Leases - Sale-Leaseback Transactions. Under the failed-sale-leaseback accounting model, we are deemed under GAAP to still own certain real estate assets sold to Cyxtera, which we must continue to reflect on our consolidated balance sheets and depreciate over the assets' remaining useful lives. Under this accounting model, we must also treat a certain amount of the pre-tax cash proceeds from the divestiture as though it were the result of a financing obligation on our consolidated balance sheets, and our consolidated results of operations must include imputed revenue associated with the portion of the real estate assets that we have not leased back and imputed interest expense on the financing obligation. A portion of the rent payments required under our leaseback arrangement with Cyxtera are recognized as reductions of the financing obligation, resulting in lower recognized rent expense than the amounts actually paid each period. Under the failed-sale-leaseback accounting model, the remaining net book value of the real estate assets must be derecognized at the end of the lease term. Please see "Leases" (ASU 2016-02) in Note 1—Background for additional information on how the new lease accounting standard will accelerate the derecognition of such amounts.

The following table reflects the assets sold to and the liabilities assumed by Cyxtera on May 1, 2017, including our estimate of the impact of failed-sale-leaseback:



	Dollars in millions
Goodwill	$	1,142
Property, plant and equipment	1,051
Other intangible assets	249
Other assets	66
Less assets recorded as part of the failed-sale-leaseback	(526		)
Total net amount of assets derecognized	$	1,982

Capital lease obligations	$	294
Other liabilities	274
Less imputed financing obligations from the failed-sale-leaseback	(628		)
Total net imputed liabilities recognized	$	(60	)

Based on our assessment of our minority stake in the limited partnership, we classified our $150 million investment in the limited partnership in other assets on our consolidated balance sheet as of September 30, 2018.

Goodwill, Customer Relationships and Other Intangible Assets Goodwill, Customer Relationships and Other Intangible Assets

9 Months Ended

Sep. 30, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill, Customer Relationships and Other Intangible Assets

Goodwill, customer relationships and other intangible assets consisted of the following:



	September 30, 2018		December 31, 2017
	(Dollars in millions)
Goodwill	$	30,770	30,475
Customer relationships, less accumulated amortization of $8,153 and $7,096	$	9,309	10,876
Indefinite-life intangible assets	$	269	269
Other intangible assets subject to amortization:
Capitalized software, less accumulated amortization of $2,547 and $2,294	1,450		1,469
Trade names and patents, less accumulated amortization of $54 and $31	138		159
Total other intangible assets, net	$	1,857	1,897

Our goodwill was derived from numerous acquisitions where the purchase price exceeded the fair value of the net assets acquired (including the acquisition described in Note 2—Acquisition of Level 3). At September 30, 2018 and December 31, 2017, the net carrying amounts of goodwill, customer relationships and other intangible assets included preliminary estimates of $19.3 billion and $20.1 billion, respectively, as a result of our Level 3 acquisition.

Total amortization expense for intangible assets for the three and nine months ended September 30, 2018 totaled $446 million and $1.3 billion, respectively, and for the three and nine months ended September 30, 2017 totaled $269 million and $820 million, respectively. As of September 30, 2018, the gross carrying amount of goodwill, customer relationships, indefinite-life and other intangible assets was $52.7 billion.

We estimate that total amortization expense for intangible assets (which include preliminary estimates for the intangible assets acquired from Level 3) for the years ending December 31, 2018 through 2022 will be as follows:



	(Dollars in millions)
2018 (remaining three months)	$	443
2019	1,692
2020	1,589
2021	1,158
2022	982

The following table shows the rollforward of goodwill assigned to our reportable segments from December 31, 2017 through September 30, 2018:



	Business			Consumer	Total
	(Dollars in millions)
As of December 31, 2017	$	20,197		10,278	30,475
Purchase accounting and other adjustments	353			—	353
Effect of foreign currency rate change	(58		)	—	(58	)
As of September 30, 2018	$	20,492		10,278	30,770

As of September 30, 2018, the $20.5 billion of goodwill assigned to our business reportable segment had not been allocated to our customer sales channels ((i) medium and small business, (ii) enterprise, (iii) international and global accounts and (iv) wholesale and indirect as we had not completed our valuation analysis and calculation. Our Chief Executive Officer, who is also our Chief Operating Decision Maker ("CODM"), continues to review the operational and internal reporting structure as a result of our acquisition of Level 3.

Revenue Recognition

9 Months Ended

Sep. 30, 2018

Revenue from Contract with Customer [Abstract]

Revenue Recognition

We earn most of our consolidated revenue from contracts with customers, primarily through the provision of telecommunications and other services. Revenue from contracts with customers is accounted for under Accounting Standards Codification ("ASC") 606, which we adopted on January 1, 2018 using the modified retrospective approach. We also earn revenues from leasing arrangements (primarily fiber capacity agreements) and governmental subsidy payments, neither of which are accounted for under ASC 606.

Under ASC 606, revenues are recognized when control of the promised goods or services is transferred to our customers, in an amount that reflects the consideration we expect to be entitled in exchange for those goods or services. Revenue is recognized based on the following five-step model:


•	Identification of the contract with a customer;


•	Identification of the performance obligations in the contract;


•	Determination of the transaction price;


•	Allocation of the transaction price to the performance obligations in the contract; and,


•	Recognition of revenue when, or as, we satisfy a performance obligation.

We provide an array of communications services, including VPN, Ethernet, data, broadband, private line, transport, voice, information technology and other ancillary services. We provide these services to a wide range of businesses, including global/international, enterprise, wholesale, government, small and medium business customers, as well as residential customers. Certain contracts also include the sale of equipment, which is not significant to our business.

For access services, we generally bill fixed monthly charges one month in advance to customers and recognize revenue as service is provided over the contract term in alignment with the customer's receipt of service. For usage, installation and other ancillary services, we generally bill in arrears and recognize revenue as usage or delivery occurs. In most cases, the amount invoiced for our service offerings constitutes the price that would be billed on a standalone basis. To the extent certain products or services are discounted as a part of a bundle arrangement, the bundle discounts are included in our calculation of the total transaction price with the customer, which is allocated to the various services in the bundle offering based on the estimated selling price of services included in each bundle combination.

Under ASC 606, we recognize revenue for services when we provide the applicable service or when control is transferred. Recognition of certain payments received in advance of services being provided is deferred until the service is provided. These advance payments include certain activation and certain installation charges. If the activation and installation charges are not separate performance obligations, we recognize as revenue over the actual or expected contract term using historical experience, which ranges from one year to seven years depending on the service. In most cases, termination fees or other fees on existing contracts that are negotiated in conjunction with new contracts are deferred and recognized over the new contract term. A performance obligation is a promise in a contract with a customer to provide a good or service to the customer. We recognize revenue for services when we satisfy our performance obligation.

Promotional or performance-based incentive payments are estimated at contract inception (and updated on a periodic basis as needed) and accounted for as variable consideration. In certain cases, customers may be permitted to modify their contracts without incurring a penalty. We evaluate the change in scope or price to identify whether the modification should be treated as a separate contract, whether the modification is a termination of the existing contract and creation of a new contract, or if it is a change to the existing contract. The impact of contract modifications has not been significant to our results in 2018.

Customer contracts are evaluated to determine whether the performance obligations are separable. If the performance obligations are deemed separable and separate earnings processes exist, the total transaction price that we expect to receive with the customer is allocated to each performance obligation based on its relative standalone selling price. The revenue associated with each performance obligation is then recognized as earned. The portion of any advance payment allocated to the service based upon its relative selling price is recognized ratably over the contract term.

We periodically sell optical capacity on our network. These transactions are structured as indefeasible rights of use, commonly referred to as IRUs, which are the exclusive right to use a specified amount of capacity or fiber for a specified term, typically 10 to 20 years. In most cases, we account for the cash consideration received on transfers of optical capacity as ASC 606 revenue which we recognize ratably over the term of the agreement. Dark fiber is accounted for as non-ASC 606 lease revenue, which we also recognize ratably over the term of the agreement. We do not recognize revenue on any contemporaneous exchanges of our optical capacity assets for other non-owned optical capacity assets.

In connection with offering products and services provided to the end user by third-party vendors, we review the relationship between us, the vendor and the end user to assess whether revenue should be reported on a gross or net basis. In assessing whether revenue should be reported on a gross or net basis, we consider whether we act as a principal in the transaction and control the goods and services used to fulfill the performance obligations associated with the transaction. Based on our agreement with DIRECTV, we offer this service through a sales agency relationship which we report on a net basis.

We have service level commitments pursuant to contracts with certain of our customers. To the extent that such service levels are not achieved or are otherwise disputed due to performance or service issues or other service interruptions or conditions, we will estimate the amount of credits to be issued and record a corresponding reduction to revenues in the period that the service level commitment was not met.

Customer payments are made based on billing schedules included in our customer contracts, which is typically on a monthly basis. For certain products or services and customer types, payment is required before products or services are provided.

Comparative Results

During the three months ended September 30, 2018, we identified and corrected certain issues in the accounting system we utilize in calculating the effects of ASC 606. Our revenue for the three months ended September 30, 2018 includes an adjustment of $43 million that is attributable to the six months ended June 30, 2018.

The following tables present our reported results under ASC 606 and a reconciliation to results using the historical accounting method:



	Three Months Ended September 30, 2018
	(Dollars in millions, except per share amounts and shares in thousands)
	Reported Balances as of September 30, 2018		Impact of ASC 606		ASC 605 Historical Adjusted Balances
Operating revenues	$	5,818	(14	)	$	5,804
Cost of services and products (exclusive of depreciation and amortization)	2,672		8		2,680
Selling, general and administrative	967		16		983
Interest expense	557		(7	)	550
Income tax expense	57		(8	)	49
Net income	$	272	(23	)	$	249

BASIC AND DILUTED EARNINGS PER COMMON SHARE
BASIC	$	0.25	(0.02	)	0.23
DILUTED	$	0.25	(0.02	)	0.23
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
BASIC	1,066,904		—		1,066,904
DILUTED	1,072,351		—		1,072,351



	Nine Months Ended September 30, 2018
	(Dollars in millions, except per share amounts and shares in thousands)
	Reported Balances as of September 30, 2018		Impact of ASC 606		ASC 605 Historical Adjusted Balances
Operating revenues	$	17,665	12		$	17,677
Cost of services and products (exclusive of depreciation and amortization)	8,205		18		8,223
Selling, general and administrative	3,191		42		3,233
Interest expense	1,638		(7	)	1,631
Income tax expense	123		(11	)	112
Net income	$	679	(30	)	$	649

BASIC AND DILUTED EARNINGS PER COMMON SHARE
BASIC	$	0.64	(0.03	)	0.61
DILUTED	$	0.63	(0.03	)	0.60
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
BASIC	1,065,410		—		1,065,410
DILUTED	1,069,726		—		1,069,726

The following table presents a reconciliation of certain consolidated balance sheet captions under ASC 606 to the balance sheet results using the historical accounting method:



	As of September 30, 2018
	(Dollars in millions)
	Reported Balances as of September 30, 2018		Impact of ASC 606		ASC 605 Historical Adjusted Balances
Other current assets	$	1,237	(390	)	$	847
Other long-term assets, net	1,014		(93	)	921
Deferred revenue	2,547		(101	)	2,446
Deferred income taxes, net	2,502		(127	)	2,375
Other long-term liabilities	1,075		122		1,197
Retained earnings	777		(377	)	400

Disaggregated Revenue by Service Offering

The following tables provide disaggregation of revenue from contracts with customers based on service offerings for the three and nine months ended September 30, 2018, respectively. It also shows the amount of revenue that is not subject to ASC 606, but is instead governed by other accounting standards. The adjustment of $43 million noted above was included in the revenue of the consumer segment for the three months ended September 30, 2018; $34 million was recorded to voice and collaboration and $9 million was recorded to transport and infrastructure.



	Three Months Ended September 30, 2018
	(Dollars in millions)
	Total Revenue		Adjustments for Non-ASC 606 Revenue ⁽⁸⁾			Total Revenue from Contracts with Customers
Business segment
IP & Data Services ⁽¹⁾	$	1,726	—			$	1,726
Transport & Infrastructure ⁽²⁾	1,331		(71		)	1,260
Voice & Collaboration ⁽³⁾	1,075		—			1,075
IT & Managed Services ⁽⁴⁾	153		—			153
Total business segment revenues	4,285		(71		)	4,214

Consumer segment
IP & Data Services ⁽⁵⁾	70		(9		)	61
Transport & Infrastructure ⁽⁶⁾	720		(54		)	666
Voice & Collaboration ⁽³⁾	565		—			565
Total consumer segment revenues	1,355		(63		)	1,292

Non-segment revenues
Regulatory revenues ⁽⁷⁾	178		(178		)	—
Total non-segment revenues	178		(178		)	—

Total revenues	$	5,818	$	(312	)	$	5,506

Timing of Revenue
Goods transferred at a point in time						$	51
Services performed over time						5,455
Total revenues from contracts with customers						$	5,506



	Nine Months Ended September 30, 2018
	(Dollars in millions)
	Total Revenue		Adjustments for Non-ASC 606 Revenue ⁽⁸⁾		Total Revenue from Contracts with Customers
Business segment
IP & Data Services ⁽¹⁾	$	5,212	—		$	5,212
Transport & Infrastructure ⁽²⁾	4,021		(217	)	3,804
Voice & Collaboration ⁽³⁾	3,324		—		3,324
IT & Managed Services ⁽⁴⁾	476		—		476
Total business segment revenues	13,033		(217	)	12,816

Consumer segment
IP & Data Services ⁽⁵⁾	249		(25	)	224
Transport & Infrastructure ⁽⁶⁾	2,171		(159	)	2,012
Voice & Collaboration ⁽³⁾	1,666		—		1,666
Total consumer segment revenues	4,086		(184	)	3,902

Non-segment revenues
Regulatory revenues ⁽⁷⁾	546		(546	)	—
Total non-segment revenues	546		(546	)	—

Total revenues	$	17,665	(947	)	$	16,718

Timing of Revenue
Goods transferred at a point in time					$	132
Services performed over time					16,586
Total revenues from contracts with customers					$	16,718



(1	)	Includes primarily VPN data network, Ethernet, IP, video and ancillary revenues.
(2	)	Includes primarily broadband, private line (including business data services), colocation and data centers, wavelength and ancillary revenues.
(3	)	Includes local, long-distance and other ancillary revenues.
(4	)	Includes IT services and managed services revenues.
(5	)	Includes retail video revenues (including our facilities-based video revenues).
(6	)	Includes primarily broadband and equipment sales and professional services revenues.
(7	)	Includes CAF Phase I, CAF Phase 2, federal and state USF support revenue, sublease rental income and failed-sale leaseback income.
(8	)	Includes regulatory revenues, lease revenues, sublease rental income, revenue from fiber capacity lease arrangements and failed sale leaseback income, which are not within the scope of ASC 606.

Customer Receivables and Contract Balances

The following table provides balances of customer receivables, contract assets and contract liabilities as of September 30, 2018 and January 1, 2018:



	September 30, 2018		January 1, 2018
	(Dollars in millions)
Customer receivables⁽¹⁾	$	2,436	2,504
Contract liabilities	716		623
Contract assets	352		255

⁽¹⁾Gross customer receivables of $2.6 billion and $2.7 billion, net of allowance for doubtful accounts of $153 million and $155 million, at September 30, 2018 and January 1, 2018, respectively.

Contract liabilities are consideration we have received from our customers in advance of providing goods or services promised in the future. We defer recognizing this consideration as revenue until we have satisfied the related performance obligation to the customer. Contract liabilities include recurring services billed one month in advance and installation and maintenance charges that are deferred and recognized over the actual or expected contract term, which ranges from one to seven years depending on the service. Contract liabilities are included within deferred revenue in our consolidated balance sheet.

Performance Obligations

We do not disclose the value of unsatisfied performance obligations for contracts for which we recognize revenue at the amount to which we have the right to invoice for services performed (for example, uncommitted usage or non-recurring charges associated with professional or technical services to be completed), or contracts that are classified as leasing arrangements that are not subject to ASC 606.

As of September 30, 2018, our estimated revenue expected to be recognized in the future related to performance obligations associated with customer contracts that are unsatisfied (or partially satisfied) is approximately $9.2 billion. We expect to recognize approximately 73% of this revenue through 2020, with the balance recognized thereafter.

Contract Costs

The following table provides changes in our contract acquisition costs and fulfillment costs:



	Three Months Ended September 30, 2018					Nine Months Ended September 30, 2018
	(Dollars in millions)
	Acquisition Costs			Fulfillment Costs		Acquisition Costs		Fulfillment Costs
Beginning of period balance	$	286		161		268		133
Costs incurred	53			46		152		105
Amortization	(44		)	(34	)	(125	)	(65	)
End of period balance	$	295		173		295		173

Acquisition costs include commission fees paid to employees as a result of obtaining contracts. Fulfillment costs include third party and internal costs associated with the provision, installation and activation of telecommunications services to customers, including labor and materials consumed for these activities.

Deferred acquisition and fulfillment costs are amortized based on the transfer of services on a straight-line basis over the average customer life of 30 months for consumer customers and 12 to 60 months for business customers and are included in cost of services and products and selling, general and administrative expenses in our consolidated statement of operations. The amount of these deferred costs that are anticipated to be amortized in the next twelve months are included in other current assets on our consolidated balance sheets. The amount of deferred costs expected to be amortized beyond the next twelve months is included in other non-current assets on our consolidated balance sheets. We recognize incremental costs of obtaining contracts as an expense when incurred if the amortization period of the assets is less than one year. Deferred acquisition and fulfillment costs are assessed for impairment on a quarterly basis. During the three months ended September 30, 2018 we made a $45 million adjustment to the beginning balance of the fulfillment costs shown in the table above for additional fulfillment costs we identified that should have been considered in our adoption. The impact to our expenses was less than $3 million for both the three and nine months ended September 30, 2018.

Long-Term Debt and Credit Facilities

9 Months Ended

Sep. 30, 2018

Debt Disclosure [Abstract]

Long-Term Debt and Credit Facilities

The following chart reflects our consolidated long-term debt, including unamortized discounts and premiums and unamortized debt issuance costs, but excluding intercompany debt:



	Interest Rates⁽¹⁾	Maturities	September 30, 2018			December 31, 2017
			(Dollars in millions)
Senior Secured Debt:
CenturyLink, Inc.
2017 Revolving Credit Facility⁽²⁾	4.898% - 4.908%	2022	$	590		405
Term Loan A	4.992%	2022	1,643			1,575
Term Loan A-1	4.992%	2022	356			370
Term Loan B	4.992%	2025	5,955			6,000
Subsidiaries:
Level 3 Financing, Inc.
Tranche B 2024 Term Loan ⁽³⁾	4.432%	2024	4,611			4,611
Embarq Corporation subsidiaries
First mortgage bonds	7.125% - 8.370%	2023 - 2025	138			151
Senior Notes and Other Debt:
CenturyLink, Inc.
Senior notes	5.625% - 7.650%	2019 - 2042	8,115			8,125
Subsidiaries:
Level 3 Financing, Inc.
Senior notes	5.125% - 6.125%	2021 - 2026	5,315			5,315
Level 3 Parent, LLC
Senior notes	5.125% - 6.1250%	2022	600			600
Qwest Corporation
Senior notes	6.125% - 7.750%	2021 - 2057	5,955			7,294
Term loan	4.250%	2025	100			100
Qwest Capital Funding, Inc.
Senior notes	6.500% - 7.750%	2018 - 2031	979			981
Embarq Corporation and subsidiary
Senior note	7.995%	2036	1,485			1,485
Other	9.000%	2019	150			150
Capital lease and other obligations	Various	Various	825			891
Unamortized premiums and other, net			2			23
Unamortized debt issuance costs			(292		)	(350	)
Total long-term debt			36,527			37,726
Less current maturities			(778		)	(443	)
Long-term debt, excluding current maturities			$	35,749		37,283

______________________________________________________________________


(1)	As ofSeptember 30, 2018.


(2)	The weighed-average interest rate payable on our outstanding revolving line of credit borrowings at December 31, 2017 was 4.186%. The aggregate amount of outstanding revolving line of credit borrowings typically change on a regular basis.


(3)	The Tranche B 2024 Term Loan is a secured obligation and is guaranteed by Level 3 Parent, LLC and certain other subsidiaries. The Tranche B 2024 Term Loan had an interest rate of 4.432% as of September 30, 2018 and 3.557% as of December 31, 2017. The interest rate on the Tranche B 2024 Term Loan is set with a minimum London Interbank Offered Rate ("LIBOR") of zero percent.

Long-Term Debt Maturities

Set forth below is the aggregate principal amount of our long-term debt (excluding unamortized discounts, net and unamortized debt issuance costs) maturing during the following years:



	(Dollars in millions)⁽¹⁾⁽²⁾
2018 (remaining three months)	$	241
2019	651
2020	1,202
2021	3,115
2022	5,323
2023 and thereafter	25,785
Total long-term debt	$	36,317

_______________________________________________________________________________

(1)

In Note 3—Sale of Data Centers and Colocation Business, we describe an imputed financing obligation. The amount outstanding on that imputed financing obligation at September 30, 2018 was $568 million. The aggregate maturities of long-term debt do not include $499 million of this obligation, which prior to the end of the lease term on April 30, 2020, will be derecognized along with the remaining net book value of the associated real estate assets.


(2)	Actual principal paid in any year may differ due to the possible future refinancing of outstanding debt or the issuance of new debt. The projected amounts in the table also exclude any impacts from any further acquisitions.

Repayments

During the three months ended September 2018, we retired approximately $1.3 billion in debt securities including approximately $164 million of Qwest 7.5% Notes due 2051, $925 million of Qwest 7.0% Notes due 2052, and $250 million of Qwest 7.25% Notes due 2035.

Covenants

Certain of our debt instruments contain affirmative and negative covenants. Debt at CenturyLink, Inc., Level 3 Parent, LLC, and Level 3 Financing, Inc. contain more extensive covenants including, among other things and subject to certain exceptions, restrictions on their ability to declare or pay dividends, repay certain other indebtedness, create liens, incur additional indebtedness, make investments, engage in transactions with their affiliates, dispose of assets and merge or consolidate with any other person. Also, CenturyLink, Inc. and certain of its affiliates will be required to offer to purchase certain of their respective outstanding debt under certain circumstances in connection with certain specified "change of control" transactions.

Certain of our debt instruments contain cross acceleration provisions.

Compliance

As of September 30, 2018, we were in compliance with the provisions and financial covenants in our material debt agreements.

Other

For additional information on our long-term debt and credit facilities, see Note 5—Long-Term Debt and Credit Facilities to our consolidated financial statements in Item 8 of Part II of our annual report on Form 10-K for the year ended December 31, 2017.

Severance and Leased Real Estate

9 Months Ended

Sep. 30, 2018

Restructuring and Related Activities [Abstract]

Severance and Leased Real Estate

Periodically, we reduce our workforce and accrue liabilities for the related severance costs. These workforce reductions result primarily from the progression or completion of our post-acquisition integration plans, increased competitive pressures, cost reduction initiatives, process improvements through automation and reduced workload demands due to the loss of customers purchasing certain services.

We have recognized liabilities to reflect our estimates of the fair values of the existing lease obligations for real estate which we have ceased using, net of estimated sublease rentals. At September 30, 2018, the current and noncurrent portions of our leased real estate accrual were $21 million and $87 million, respectively. The remaining lease terms range from 0.26 years to 12.3 years, with a weighted-average of 7.0 years.

Changes in our accrued liabilities for severance expenses and leased real estate were as follows:



	Severance			Real Estate
	(Dollars in millions)
Balance at December 31, 2017	$	33		64
Accrued to expense	126			60
Payments, net	(137		)	(16	)
Balance at September 30, 2018	$	22		108

Employee Benefits

9 Months Ended

Sep. 30, 2018

Retirement Benefits [Abstract]

Employee Benefits

Net periodic benefit (income) expense for our qualified and non-qualified pension plans included the following components:



	Pension Plans
	Three Months Ended September 30,					Nine Months Ended September 30,
	2018			2017		2018		2017
	(Dollars in millions)
Service cost	$	17		16		49		47
Interest cost	99			102		296		308
Expected return on plan assets	(171		)	(166	)	(513	)	(499	)
Recognition of prior service credit	(2		)	(2	)	(6	)	(6	)
Recognition of actuarial loss	45			51		135		154
Net periodic pension benefit (income) expense	$	(12	)	1		(39	)	4

Net periodic benefit expense for our post-retirement benefit plans included the following components:



	Post-Retirement Benefit Plans
	Three Months Ended September 30,				Nine Months Ended September 30,
	2018			2017	2018		2017
	(Dollars in millions)
Service cost	$	4		4	13		13
Interest cost	24			25	73		75
Expected return on plan assets	(1		)	—	(1	)	(1	)
Recognition of prior service cost	5			5	15		15
Net periodic post-retirement benefit expense	$	32		34	100		102

Benefits paid by our qualified pension plan are paid through a trust that holds all plan assets. Based on current laws and circumstances, we do not expect any contributions to be required for our qualified pension plan during the remainder of 2018. However, we made voluntary contributions of $500 million to the trust for our qualified pension plan during the nine months ended September 30, 2018, including $400 million during the third quarter of 2018.

Earnings Per Common Share

9 Months Ended

Sep. 30, 2018

Earnings Per Share [Abstract]

Earnings Per Common Share

Basic and diluted earnings per common share were calculated as follows:



	Three Months Ended September 30,					Nine Months Ended September 30,
	2018			2017		2018		2017
	(Dollars in millions, except per share amounts, shares in thousands)
Income (Numerator):
Net income	$	272		92		679		272
Earnings applicable to non-vested restricted stock	—			—		—		—
Net income applicable to common stock for computing basic earnings per common share	272			92		679		272
Net income as adjusted for purposes of computing diluted earnings per common share	$	272		92		679		272
Shares (Denominator):
Weighted-average number of shares:
Outstanding during period	1,080,589			549,618		1,077,712		548,779
Non-vested restricted stock	(13,685		)	(8,097	)	(12,302	)	(7,666	)
Weighted-average shares outstanding for computing basic earnings per common share	1,066,904			541,521		1,065,410		541,113
Incremental common shares attributable to dilutive securities:
Shares issuable under convertible securities	10			10		10		10
Shares issuable under incentive compensation plans	5,437			432		4,306		756
Number of shares as adjusted for purposes of computing diluted earnings per common share	1,072,351			541,963		1,069,726		541,879
Basic earnings per common share	$	0.25		0.17		0.64		0.50
Diluted earnings per common share	$	0.25		0.17		0.63		0.50

Our calculation of diluted earnings per common share excludes shares of common stock that are issuable upon exercise of stock options when the exercise price is greater than the average market price of our common stock. We also exclude unvested restricted stock awards that are anti-dilutive as a result of unrecognized compensation cost. Such shares averaged 1.5 million and 5.1 million for the three months ended September 30, 2018 and 2017, respectively, and averaged 3.0 million and 4.2 million for the nine months ended September 30, 2018 and 2017, respectively.

Fair Value of Financial Instruments

9 Months Ended

Sep. 30, 2018

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

The following table presents the carrying amounts and estimated fair values of our long-term debt, excluding capital lease and other obligations, as well as the input level used to determine the fair values indicated below:



		September 30, 2018			December 31, 2017
	Input Level	Carrying Amount		Fair Value	Carrying Amount	Fair Value
		(Dollars in millions)
Liabilities—Long-term debt, excluding capital lease and other obligations	2	$	35,702	35,750	36,835	36,402

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Segment Information

9 Months Ended

Sep. 30, 2018

Segment Reporting [Abstract]

Segment Information

Segment Data

In connection with our acquisition of Level 3 (discussed further in Note 2—Acquisition of Level 3), effective November 1, 2017, we implemented a new organization structure and began managing our operations in two segments: business and consumer. Our consumer segment remains substantially similar under this reorganization, and our newly reorganized business segment includes the Legacy CenturyLink enterprise segment operations and the Legacy Level 3 operations. In addition, we reassigned our information technology, managed hosting, cloud hosting and hosting area network operations back into the business segment, thereby eliminating a former non-reportable operating segment. At September 30, 2018, we had the following two reportable segments:

•

Business Segment. This segment consists generally of providing products and services to small, medium and enterprise business, wholesale, government and international customers, including other communication providers. Our products and services offered to these customers include our local and long-distance voice, VPN data network, private line (including business data services), Ethernet, information technology, wavelength, broadband, colocation and data center services, managed services, professional and other services provided in connection with selling equipment, network security and various other ancillary services, all of which are described further under "Products and Services Categories"; and


•	Consumer Segment. This segment consists generally of providing products and services to residential customers. Our products and services offered to these customers include our broadband, local and long-distance voice, video and other ancillary services.

The results of our two reportable segments, business and consumer, are summarized below:



	Three Months Ended September 30,					Nine Months Ended September 30,
	2018			2017		2018		2017
	(Dollars in millions)
Total reportable segment revenues	$	5,640		3,845		17,119		11,789
Total reportable segment expenses	2,969			2,197		9,244		6,572
Total reportable segment adjusted EBITDA	$	2,671		1,648		7,875		5,217
Total margin percentage	47		%	43	%	46	%	44	%

Business segment:
Revenues	$	4,285		2,425		13,033		7,485
Expenses	2,446			1,537		7,540		4,641
Adjusted EBITDA	$	1,839		888		5,493		2,844
Margin percentage	43		%	37	%	42	%	38	%
Consumer segment:
Revenues	$	1,355		1,420		4,086		4,304
Expenses	523			660		1,704		1,931
Adjusted EBITDA	$	832		760		2,382		2,373
Margin percentage	61		%	54	%	58	%	55	%

Our CODM continues to review the operational and internal reporting structure as a result of our acquisition of Level 3 (See Note 2—Acquisition of Level 3).

Product and Service Categories

We categorize our products, services and revenues among the following five categories:


•	IP and data services, which include primarily VPN data networks, Ethernet, IP, video (including our facilities-based video services, CDN services and Vyvx broadcast services) and other ancillary services;


•	Transport and infrastructure, which include broadband, private line (including business data services), data center facilities and services, including cloud, hosting and application management solutions, wavelength, equipment sales and professional services, network security services, dark fiber services and other ancillary services;


•	Voice and collaboration, which includes primarily local and long-distance voice, including wholesale voice, and other ancillary service;


•	IT and managed services, which include information technology services and managed services, which may be purchased in conjunction with our other network services; and

•

Regulatory revenues, which consists of Universal Service Fund ("USF") and Connect America Fund ("CAF") support payments and other operating revenues. We receive federal support payments from both federal and state USF programs and from the federal CAF program. The USF and CAF support payments are government subsidies designed to reimburse us for various costs related to certain telecommunications services. We generate other operating revenues from the leasing and subleasing of space in our office buildings, warehouses and other properties and from rental income associated with the failed-sale-leaseback. Because we centrally manage the activities that generate these regulatory revenues, these revenues are not included in our segment revenues.

Our operating revenue detail for our products and services consisted of the following categories:



	Three Months Ended September 30,			Nine Months Ended September 30,
	2018		2017	2018	2017
	(Dollars in millions)
Business segment
IP and data services ⁽¹⁾	$	1,726	755	5,212	2,256
Transport and infrastructure ⁽²⁾	1,331		735	4,021	2,426
Voice and collaboration ⁽³⁾	1,075		765	3,324	2,319
IT and managed services ⁽⁴⁾	153		170	476	484
Total business segment revenues	4,285		2,425	13,033	7,485

Consumer segment
IP and data services ⁽⁵⁾	70		98	249	308
Transport and infrastructure ⁽⁶⁾	720		697	2,171	2,063
Voice and collaboration ⁽³⁾	565		625	1,666	1,933
Total consumer segment revenues	1,355		1,420	4,086	4,304

Non-segment revenues
Regulatory revenues ⁽⁷⁾	178		189	546	544
Total non-segment revenues	178		189	546	544

Total revenues	$	5,818	4,034	17,665	12,333

______________________________________________________________________



(1)	Includes primarily VPN data network, Ethernet, IP, video and ancillary revenues.
(2)	Includes primarily broadband, private line (including business data services), colocation and data centers, wavelength and ancillary revenues.
(3)	Includes local, long-distance and other ancillary revenues.
(4)	Includes IT services and managed services revenues.
(5)	Includes retail video revenues (including our facilities-based video revenues).
(6)	Includes primarily broadband and equipment sales and professional services revenues.
(7)	Includes CAF Phase I, CAF Phase 2, federal and state USF support revenue, sublease rental income and failed-sale leaseback income.

We recognize revenues in our consolidated statements of operations for certain USF surcharges and transaction taxes that we bill to our customers. Our consolidated statements of operations also reflect the offsetting expense for the amounts we remit to the government agencies. The total amount of such surcharges and transaction taxes that we included in revenues aggregated $221 million and $129 million for the three months ended September 30, 2018 and 2017, respectively, and $698 million and $392 million for the nine months ended September 30, 2018 and 2017, respectively. These USF surcharges, where we record revenue, and transaction taxes are assigned to the products and services categories of each segment based on the underlying revenues. We also act as a collection agent for certain other USF and transaction taxes that we are required by government agencies to bill our customers, for which we do not record any revenue or expense because we only act as a pass-through agent.

Allocations of Revenues and Expenses

Our segment revenues include all revenues from our business and consumer segments as described in more detail above. Our segment revenues are based upon each customer's classification. We report our segment revenues based upon all services provided to that segment's customers. Our segment expenses include specific expenses incurred as a direct result of providing services and products to segment customers, along with selling, general and administrative expenses that are (i) directly associated with specific segment customers or activities and (ii) allocated expenses, which include network expenses, facilities expenses and other expenses such as fleet and real estate expenses. We do not assign depreciation and amortization expense or impairments to our segments, as the related assets and capital expenditures are centrally managed and are not monitored by or reported to the CODM by segment. Generally speaking, severance expenses, restructuring expenses and certain centrally managed administrative functions (such as finance, information technology, legal and human resources) are not assigned to our segments. Interest expense is also excluded from segment results because we manage our financing on a consolidated basis and have not allocated assets or debt to specific segments. Other income and expense items are not monitored as a part of our segment operations and are therefore excluded from our segment results.

The following table reconciles total reportable segment adjusted EBITDA to net income:



	Three Months Ended September 30,					Nine Months Ended September 30,
	2018			2017		2018		2017
	(Dollars in millions)
Total reportable segment adjusted EBITDA	$	2,671		1,648		7,875		5,217
Regulatory revenues	178			189		546		544
Depreciation and amortization	(1,285		)	(910	)	(3,858	)	(2,739	)
Other operating expenses	(670		)	(440	)	(2,152	)	(1,537	)
Total other expense, net	(565		)	(348	)	(1,609	)	(999	)
Income before income tax expense	329			139		802		486
Income tax expense	57			47		123		214
Net income	$	272		92		679		272

Commitments and Contingencies and Other Items	9 Months Ended
Commitments and Contingencies and Other Items	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies and Other Items	Commitments and Contingencies and Other Items We are subject to various claims, legal proceedings and other contingent liabilities, including the matters described below, which individually or in the aggregate could materially affect our financial condition, future results of operations or cash flows. As a matter of course, we are prepared to both litigate these matters to judgment as needed, as well as to evaluate and consider reasonable settlement opportunities. Irrespective of its merits, litigation may be both lengthy and disruptive to our operations and could cause significant expenditure and diversion of management attention. We review our litigation accrual liabilities on a quarterly basis, but in accordance with applicable accounting guidelines only establish accrual liabilities when losses are deemed probable and reasonably estimable and only revise previously-established accrual liabilities when warranted by changes in circumstances, in each case based on then-available information. As such, as of any given date we could have exposure to losses under proceedings as to which no liability has been accrued or as to which the accrued liability is inadequate. Amounts accrued for our litigation contingencies at September 30, 2018 aggregated to approximately $138 million and are included in “Other” current liabilities and “Other Liabilities” in our consolidated balance sheet as of such date. The establishment of an accrual does not mean that actual funds have been set aside to satisfy a given contingency. Thus, the resolution of a particular contingency for the amount accrued could have no effect on our results of operations but nonetheless could have an adverse effect on our cash flows. In this Note, when we refer to a class action as "putative" it is because a class has been alleged, but not certified in that matter. Shareholder Litigation CenturyLink and certain members of the CenturyLink Board of Directors have been named as defendants in a putative shareholder class action lawsuit filed on January 11, 2017 in the 4th Judicial District Court of the State of Louisiana, Ouachita Parish, captioned Jeffery Tomasulo v. CenturyLink, Inc., et al. The complaint asserts, among other things, that the members of CenturyLink’s Board allegedly breached their fiduciary duties to the CenturyLink shareholders in approving the Level 3 merger agreement and, more particularly, that: the consideration that CenturyLink agreed to pay to Level 3 stockholders in the transaction is allegedly unfairly high; the CenturyLink directors allegedly had conflicts of interest in negotiating and approving the transaction; and the disclosures set forth in our preliminary joint proxy statement/prospectus filed in December 2016 are insufficient in that they allegedly fail to contain material information concerning the transaction. The complaint seeks, among other things, a declaration that the members of the CenturyLink Board have breached their fiduciary duties, corrective disclosure, rescissory or other damages and equitable relief, including rescission of the transaction. On February 13, 2017, the parties entered into a memorandum of understanding providing for the settlement of the lawsuit. The proposed settlement is subject to court approval, among other conditions, and the amount of the settlement is not material to our consolidated financial statements. CenturyLink and certain CenturyLink board members and officers were named as defendants in a putative shareholder class action lawsuit filed on June 12, 2018 in the Boulder County District Court of the state of Colorado, captioned Houser et al. v. CenturyLink, et al. The complaint asserts claims on behalf of a putative class of former Level 3 shareholders who became CenturyLink shareholders as a result of the transaction. It alleges that the proxy statement provided to the Level 3 shareholders failed to disclose material information of several kinds, including information about strategic revenues, customer loss rates, and customer account issues, among other items. The complaint seeks damages, costs and fees, rescission, rescissory damages, and other equitable relief. Switched Access Disputes Subsidiaries of CenturyLink, Inc. are among hundreds of companies involved in an industry-wide dispute, raised in nearly 100 federal lawsuits (filed between 2014 and 2016) that have been consolidated as In Re: IntraMTA Switched Access Charges Litigation, in the United States District Court for the Northern District of Texas for pretrial procedures. The disputes relate to switched access charges that local exchange carriers ("LECs") collect from interexchange carriers ("IXCs") for IXCs' use of LEC's access services. In the lawsuits, various IXCs assert that LECs are prohibited from collecting access charges when IXCs exchange certain types of calls between mobile and wireline devices. Some of these IXCs seek refunds for access charges previously paid and declaratory relief from future access charges. In November 2015, the court rejected the IXCs' claims under federal law and entered final judgments against the IXCs on the LECs' claims for unpaid access charges and for late payment charges. The cases are now on appeal before the U.S. Court of Appeals for the Fifth Circuit. Separately, some of the defendants have petitioned the FCC to address these issues on an industry-wide basis. As both an IXC and a LEC, we both pay and assess significant amounts of the charges in question. The outcome of these disputes and lawsuits, as well as any related regulatory proceedings that could ensue, could affect our financial results and are currently not predictable. State Tax Suits Several Missouri municipalities have, beginning in May 2012, asserted claims alleging underpayment of taxes against CenturyLink, Inc. and several of its subsidiaries in a number of proceedings filed in the Circuit Court of St. Louis County, Missouri. These municipalities are seeking, among other things, declaratory relief regarding the application of business license and gross receipts taxes and back taxes from 2007 to the present, plus penalties and interest. In a February 2017 ruling in connection with one of these pending cases, the court entered an order awarding plaintiffs $4 million and broadening the tax base on a going-forward basis. We have appealed that ruling. In a June 2017 ruling in connection with another one of these pending cases, the court made findings which, if not overturned, will result in a tax liability to us well in excess of the contingent liability we have established. In due course, we plan to appeal that decision. We continue to vigorously defend against these claims. Billing Practices Suits In June 2017, a former employee filed an employment lawsuit against us claiming that she was wrongfully terminated for alleging that we charged some of our retail customers for products and services they did not authorize. Starting shortly thereafter and continuing since then, and based in part on the allegations made by the former employee, several legal proceedings have been filed. In June 2017, McLeod v. CenturyLink, a putative consumer class action, was filed against us in the U.S. District Court for the Central District of California alleging that we charged some of our retail customers for products and services they did not authorize. A number of other complaints asserting similar claims have been filed in other federal and state courts, as well. The lawsuits assert claims including fraud, unfair competition, and unjust enrichment. Also in June 2017, Craig. v. CenturyLink, Inc., et al., a putative securities investor class action, was filed in U.S. District Court for the Southern District of New York, alleging that we failed to disclose material information regarding improper sales practices, and asserting federal securities law claims. A number of other cases asserting similar claims have also been filed. Both the putative consumer class actions and the putative securities investor class actions have been transferred to the U.S. District Court for the District of Minnesota for coordinated and consolidated pretrial proceedings as In Re: CenturyLink Sales Practices and Securities Litigation. Beginning June 2017, we also received several shareholder derivative demands addressing related topics. In August 2017, the Board of Directors formed a special litigation committee of outside directors to address the allegations of impropriety contained in the shareholder derivative demands. In April 2018, the special litigation committee concluded its review of the derivative demands and declined to take further action. Since then, another demand has been received, and six derivative cases were filed. Two of these cases, Castagna v. Post and Pinsly v. Post, were filed in Louisiana state court in the Fourth Judicial District Court for the Parish of Ouachita; four others, Ault v. Post, Barbree v. Post, Flanders v. Post, and Palkon v. Boulet, were filed in Louisiana federal court in the Monroe Division of the Western District of Louisiana. These cases have been brought on behalf of CenturyLink against certain current and former officers and directors of the Company and seek damages for alleged breaches of fiduciary duties. In July 2017, the Minnesota state attorney general filed State of Minnesota v. CenturyTel Broadband Services LLC, et al. in the Asoka County Minnesota District Court, alleging claims of fraud and deceptive trade practices relating to improper consumer sales practices. The suit seeks an order of restitution on behalf of all CenturyLink customers, civil penalties, injunctive relief, and costs and fees. Additionally, we have received and responded to information requests and inquiries from other states. Peruvian Tax Litigation In 2005, the Peruvian tax authorities ("SUNAT") issued tax assessments against one of our Peruvian subsidiaries asserting $26 million, of additional income tax withholding and value-added taxes ("VAT"), penalties and interest for calendar years 2001 and 2002 on the basis that the Peruvian subsidiary incorrectly documented its importations. After taking into account the developments described below, as well as the accrued interest and foreign exchange effects, the total amount of exposure is $13 million at September 30, 2018. We challenged the assessments via administrative and then judicial review processes. In October 2011, the highest administrative review tribunal (the Tribunal) decided the central issue underlying the 2002 assessments in SUNAT's favor. We appealed the Tribunal's decision to the first judicial level, which decided the central issue in favor of Level 3. SUNAT and we filed cross-appeals with the court of appeal. In May 2017, the court of appeal issued a decision reversing the first judicial level. In June 2017, we filed an appeal of the decision to the Supreme Court of Justice, the final judicial level. Oral argument was held before the Supreme Court of Justice in October 2018. A decision on this case is pending. In October 2013, the Tribunal decided the central issue underlying the 2001 assessments in SUNAT’s favor. We appealed that decision to the first judicial level in Peru, which decided the central issue in favor of SUNAT. In June 2017, we filed an appeal with the court of appeal. In November 2017, the court of appeals issued a decision affirming the first judicial level and we filed an appeal of the decision to the Supreme Court of Justice. That appeal is pending. Employee Severance and Contractor Termination Disputes A number of former employees and third-party contractors have asserted a variety of claims in litigation against certain of Level 3’s Latin American subsidiaries for separation pay, severance, commissions, pension benefits, unpaid vacation pay, breach of employment contracts, unpaid performance bonuses, property damages, moral damages and related statutory penalties, fines, costs and expenses (including accrued interest, attorneys' fees and statutorily mandated inflation adjustments) as a result of their separation from Level 3 or termination of service relationships. Level 3 is vigorously defending itself against the asserted claims, which aggregate to approximately $30 million at September 30, 2018. Brazilian Tax Claims In December 2004, March 2009, April 2009 and July 2014, the São Paulo state tax authorities issued tax assessments against one of our Brazilian subsidiaries for the Tax on Distribution of Goods and Services (“ICMS”) with respect to revenue from leasing certain assets (in the case of the December 2004, March 2009 and July 2014 assessments) and revenue from the provision of Internet access services (in the case of the April 2009 and July 2014 assessments), by treating such activities as the provision of communications services, to which the ICMS tax applies. In September 2002, July 2009 and May 2012, the Rio de Janeiro state tax authorities issued tax assessments to the same Brazilian subsidiary on similar issues. We have filed objections to these assessments, arguing that the lease of assets and the provision of Internet access are not communication services subject to ICMS. The objections to the September 2002, December 2004 and March 2009 assessments were rejected by the respective state administrative courts, and we have appealed those decisions to the judicial courts. In October 2012 and June 2014, we received favorable rulings from the lower court on the December 2004 and March 2009 assessments regarding equipment leasing, but those rulings are subject to appeal by the state. No ruling has been obtained with respect to the September 2002 assessment. The objections to the April and July 2009 and May 2012 assessments are still pending final administrative decisions. The July 2014 assessment was confirmed during the fourth quarter of 2014 at the first administrative level, and we appealed this decision to the second administrative level. We are vigorously contesting all such assessments in both states and, in particular, view the assessment of ICMS on revenue from equipment leasing to be without merit. These assessments, if upheld, could result in a loss of up to $34 million at September 30, 2018 in excess of the accruals established for these matters. Qui Tam Action Level 3 was notified in late 2017 of a qui tam action pending against Level 3 Communications, Inc. and others in the United States District Court for the Eastern District of Virginia, captioned United States of America ex rel., Stephen Bishop v. Level 3 Communications, Inc. et al. The original qui tam complaint was filed under seal on November 26, 2013, and an amended complaint was filed under seal on June 16, 2014. The court unsealed the complaints on October 26, 2017. The amended complaint alleges that Level 3, principally through two former employees, submitted false claims and made false statements to the government in connection with two government contracts. The relator seeks damages in this lawsuit of approximately $50 million, subject to trebling, plus statutory penalties, pre-and-post judgment interest, and attorney’s fees. The case is currently stayed. Level 3 is evaluating its defenses to the claims. At this time, Level 3 does not believe it is probable Level 3 will incur a material loss. If, contrary to its expectations, the plaintiff prevails in this matter and proves damages at or near $50 million, and is successful in having those damages trebled, the outcome could have a material adverse effect on our results of operations in the period in which a liability is recognized and on our cash flows for the period in which any damages are paid. Several people, including two former Level 3 employees were indicted in the United States District Court for the Eastern District of Virginia on October 3, 2017, and charged with, among other things, accepting kickbacks from a subcontractor, who was also indicted, for work to be performed under a prime government contract. Of the two former employees, one entered into a plea agreement, and the other is deceased. Level 3 is fully cooperating in the government’s investigations in this matter. Letters of Credit It is customary for us to use various financial instruments in the normal course of business. These instruments include letters of credit which are conditional commitments issued on our behalf in accordance with specified terms and conditions. As of September 30, 2018 and December 31, 2017, we had outstanding letters of credit or other similar obligations of approximately $129 million and $104 million, respectively. Other Proceedings, Disputes and Contingencies From time to time, we are involved in other proceedings incidental to our business, including patent infringement allegations, administrative hearings or proceedings of state public utility commissions relating primarily to our rates or services, actions relating to employee claims, various tax issues, environmental law issues, grievance hearings before labor regulatory agencies and miscellaneous third-party tort actions. We are currently defending several patent infringement lawsuits asserted against us by non-practicing entities, many of which are seeking substantial recoveries. These cases have progressed to various stages and one or more may go to trial in the coming 24 months if they are not otherwise resolved. Where applicable, we are seeking full or partial indemnification from our vendors and suppliers. As with all litigation, we are vigorously defending these actions and, as a matter of course, are prepared to litigate these matters to judgment, as well as to evaluate and consider all reasonable settlement opportunities. We are subject to various foreign, federal, state and local environmental protection and health and safety laws. From time to time, we are subject to judicial and administrative proceedings brought by various governmental authorities under these laws. Several such proceedings are currently pending, but none individually is reasonably expected to exceed $100,000 in fines and penalties. The outcome of these other proceedings is not predictable. However, based on current circumstances, we do not believe that the ultimate resolution of these other proceedings, after considering available defenses and any insurance coverage or indemnification rights, will have a material adverse effect on us. The matters listed above in this Note do not reflect all of our contingencies. For additional information on our contingencies, see Note 16 to the financial statements included in Item 8 of Part II of our annual report on Form 10-K for the year ended December 31, 2017. The ultimate outcome of the above-described matters may differ materially from the outcomes anticipated, estimated, projected or implied by us in certain of our statements appearing above in this Note, and proceedings currently viewed as immaterial by us may ultimately materially impact us.

Other Financial Information

9 Months Ended

Sep. 30, 2018

Additional Financial Information Disclosure [Abstract]

Other Financial Information

Other Current Assets

The following table presents details of other current assets reflected in our consolidated balance sheets:



	September 30, 2018		December 31, 2017
	(Dollars in millions)
Prepaid expenses	$	379	294
Income tax receivable	79		258
Materials, supplies and inventory	131		128
Contract assets	359		128
Contract acquisition costs	155		—
Other	134		133
Total other current assets	$	1,237	941

Selected Current Liabilities

The following table presents details of other current liabilities reflected in our consolidated balance sheets:



	September 30, 2018		December 31, 2017
	(Dollars in millions)
Other current liabilities:
Accrued contributions to federal programs	$	136	74
Dividends payable	51		34
Accrued rents	41		14
Accrued rents-telephone poles	35		34
Litigation contingencies	31		45
Other	80		143
Total other current liabilities	$	374	344

Included in accounts payable at September 30, 2018 and December 31, 2017, were $58 million and $36 million, respectively, representing book overdrafts.

Accumulated Other Comprehensive Loss

9 Months Ended

Sep. 30, 2018

Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]

Accumulated Other Comprehensive Loss

Information Relating to 2018

The tables below summarize changes in accumulated other comprehensive loss recorded on our consolidated balance sheets by component for the nine months ended September 30, 2018:



	Pension Plans			Post-Retirement Benefit Plans		Foreign Currency Translation Adjustment and Other		Total
	(Dollars in millions)
Balance at December 31, 2017	$	(1,731	)	(235	)	(29	)	(1,995	)
Other comprehensive income before reclassifications	—			—		(161	)	(161	)
Amounts reclassified from accumulated other comprehensive income	97			12		—		109
Net current-period other comprehensive income	97			12		(161	)	(52	)
Cumulative effect of adoption of ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income	(375		)	(32	)	—		(407	)
Balance at September 30, 2018	$	(2,009	)	(255	)	(190	)	(2,454	)

The tables below present further information about our reclassifications out of accumulated other comprehensive loss by component for the three and nine months ended September 30, 2018:



Three Months Ended September 30, 2018	Decrease (Increase) in Net Income			Affected Line Item in Consolidated Statement of Operations
	(Dollars in millions)
Amortization of pension & post-retirement plans⁽¹⁾
Net actuarial loss	$	45		Other income (expense), net
Prior service cost	3			Other income (expense), net
Total before tax	48
Income tax benefit	(11		)	Income tax expense
Net of tax	$	37



Nine Months Ended September 30, 2018	Decrease (Increase) in Net Income			Affected Line Item in Consolidated Statement of Operations
	(Dollars in millions)
Amortization of pension & post-retirement plans⁽¹⁾
Net actuarial loss	$	135		Other income (expense), net
Prior service cost	9			Other income (expense), net
Total before tax	144
Income tax benefit	(35		)	Income tax expense
Net of tax	$	109

________________________________________________________________________


(1)	See Note 8—Employee Benefits for additional information on our net periodic benefit (expense) income related to our pension and post-retirement plans.

Information Relating to 2017

The tables below summarize changes in accumulated other comprehensive loss recorded on our consolidated balance sheets by component for the nine months ended September 30, 2017:



	Pension Plans			Post-Retirement Benefit Plans		Foreign Currency Translation Adjustment and Other		Total
	(Dollars in millions)
Balance at December 31, 2016	$	(1,895	)	(162	)	(60	)	(2,117	)
Other comprehensive income before reclassifications	—			—		20		20
Amounts reclassified from accumulated other comprehensive income	93			10		—		103
Net current-period other comprehensive income	93			10		20		123
Balance at September 30, 2017	$	(1,802	)	(152	)	(40	)	(1,994	)

The tables below present further information about our reclassifications out of accumulated other comprehensive loss by component for the three and nine months ended September 30, 2017:



Three Months Ended September 30, 2017	Decrease (Increase) in Net Income			Affected Line Item in Consolidated Statement of Operations
	(Dollars in millions)
Amortization of pension & post-retirement plans⁽¹⁾
Net actuarial loss	$	51		Other income (expense), net
Prior service cost	3			Other income (expense), net
Total before tax	54
Income tax benefit	(16		)	Income tax expense
Net of tax	$	38

________________________________________________________________________


(1)	See Note 8—Employee Benefits for additional information on our net periodic benefit (expense) income related to our pension and post-retirement plans.



Nine Months Ended September 30, 2017	Decrease (Increase) in Net Income			Affected Line Item in Consolidated Statement of Operations
	(Dollars in millions)
Amortization of pension & post-retirement plans⁽¹⁾
Net actuarial loss	$	154		Other income (expense), net
Prior service cost	9			Other income (expense), net
Total before tax	163
Income tax benefit	(60		)	Income tax expense
Net of tax	$	103

________________________________________________________________________


(1)	See Note 8—Employee Benefits for additional information on our net periodic benefit (expense) income related to our pension and post-retirement plans.

Labor Union Contracts	9 Months Ended
Labor Union Contracts	Sep. 30, 2018
Labor Union Contracts [Abstract]
Labor Union Contracts	Labor Union Contracts As of September 30, 2018, approximately 26% of our employees were members of various bargaining units represented by the Communication Workers of America ("CWA") and the International Brotherhood of Electrical Workers ("IBEW"). We believe that relations with our employees continue to be generally good. Approximately 300 (less than 1%) of our employees were subject to collective bargaining agreements that have expired as of September 30, 2018 and are currently being renegotiated.

Background (Policies)	9 Months Ended
Background (Policies)	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Consolidation policy	To simplify the overall presentation of our consolidated financial statements, we report immaterial amounts attributable to noncontrolling interests in certain of our subsidiaries as follows: (i) income attributable to noncontrolling interests in other income (expense), net, (ii) equity attributable to noncontrolling interests in additional paid-in capital and (iii) cash flows attributable to noncontrolling interests in other, net financing activities.
Reclassification policy	We reclassified certain prior period amounts to conform to the current period presentation, including the categorization of our revenues and our segment reporting. See Note 11—Segment Information for additional information. These changes had no impact on total operating revenues, total operating expenses or net income for any period.
Recently adopted accounting pronouncements and recent accounting pronouncements	Recently Adopted Accounting Pronouncements In the first quarter of 2018, we adopted Accounting Standards Update (“ASU”) 2014-09, “Revenue from Contracts with Customers”, ASU 2018-02, “Income Statement-Reporting Comprehensive Income: Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income” and ASU 2016-16, “Intra-Entity Transfers of Assets Other Than Inventory”. Each of these is described further below. Revenue Recognition In May 2014, the FASB issued ASU 2014-09 which replaces virtually all existing generally accepted accounting principles on revenue recognition and replaces them with a principles-based approach for determining revenue recognition using a new five step model. The core principle of ASU 2014-09 is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 also includes new accounting principles related to the deferral and amortization of contract acquisition and fulfillment costs. We adopted the new revenue recognition standard under the modified retrospective transition method. During the three and nine months ended September 30, 2018, we recorded a cumulative catch-up adjustment that increased our retained earnings by $49 million, net of $17 million of income taxes, and $346 million, net of $117 million of income taxes, respectively. The catch-up adjustment recorded during the three months ended September 30, 2018 resulted from the identification of additional fulfillment costs that should have been considered in our adoption and from correcting certain issues in the accounting system we utilize in calculating revenue under the new revenue recognition standard. Under ASU 2014-09, we are now deferring incremental contract acquisition and fulfillment costs and are recognizing (or amortizing) such costs over either the initial contract (plus anticipated renewal contracts to which the costs relate) or the average customer life. Deferred acquisition and fulfillment costs are amortized based on the transfer of services on a straight-line basis over the average customer life of 30 months for consumer customers and 12 to 60 months for business customers and are included in cost of services and products and selling, general and administrative expenses in our consolidated statement of operations. A portion of these costs are amortized on a portfolio basis using an average expected contract term of 30 months. The amounts of these deferred costs that are anticipated to be amortized in the next twelve months are included in other current assets on our consolidated balance sheets. See Note 5—Revenue Recognition for additional information. Comprehensive Income ASU 2018-02 provides an option to reclassify stranded tax effects within accumulated other comprehensive income to retained earnings in each period in which the effect of the change in the U.S. federal corporate income tax rate in the Act (or portion thereof) is recorded. If an entity elects to reclassify the income tax effects of the Act, the amount of that reclassification shall include the effect of the change in the U.S. federal corporate income tax rate on the gross deferred tax amounts and related valuation allowances, if any, at the date of enactment of the Act related to items remaining in accumulated other comprehensive income. The effect of the change in the U.S. federal corporate income tax rate on gross valuation allowances that were originally charged to income from continuing operations shall not be included. ASU 2018-02 is effective January 1, 2019, but early adoption is permitted and should be applied either in the period of adoption or retrospectively to each period (or periods) in which the effect of the change in the U.S. federal corporate income tax rate in the Act is recognized. We early adopted and applied ASU 2018-02 in the first quarter of 2018. The adoption of ASU 2018-02 resulted in a $407 million increase to retained earnings and in accumulated other comprehensive loss. See Note 14—Accumulated Other Comprehensive Loss for additional information. Income Taxes ASU 2016-16 eliminates the current prohibition on the recognition of the income tax effects on the transfer of assets among our subsidiaries. Prospectively, the income tax effects associated with these asset transfers, except for the transfer of inventory, will be recognized in the period the asset is transferred versus the current deferral and recognition upon either the sale of the asset to a third party or over the remaining useful life of the asset. Our adoption of ASU 2016-16 did not have a material impact to our consolidated financial statements. Recently Issued Accounting Pronouncements Retirement Benefits In August 2018, the FASB issued ASU 2018-14, "Compensation-Retirement Benefits-Defined Benefit Plans-General: Disclosure Framework-Changes to the Disclosure Requirements for Defined Benefit Plans" (“ASU 2018-14“). ASU 2018-14 eliminates requirements for certain disclosures that are not considered cost beneficial, clarifies certain required disclosures and adds additional disclosures under defined benefit pension plans and other postretirement plans. We are required to adopt this guidance beginning January 1, 2021. Early adoption is permitted. The amendments in ASU 2018-14 would need to be applied on a retrospective basis. We are currently evaluating the potential impact of the adoption of this standard on our disclosures. Goodwill Impairment In January 2017, the FASB issued ASU 2017-04, “Simplifying the Test for Goodwill Impairment” (“ASU 2017-04”). ASU 2017-04 simplifies the impairment testing for goodwill by changing the measurement for goodwill impairment. Under current rules, we are required to compute the implied fair value of goodwill to measure the impairment amount if the carrying value of a reporting unit exceeds its fair value. Under ASU 2017-04, the goodwill impairment charge will equal the excess of the reporting unit carrying value above its fair value, limited to the amount of goodwill assigned to the reporting unit. We are required to adopt the provisions of ASU 2017-04 for any goodwill impairment tests, including our required annual test, occurring after January 1, 2020, but have the option to early adopt it for any impairment test that we are required to perform. We have not determined if we will elect to early adopt the provisions of ASU 2017-04. The provisions of ASU 2017-04 would not have affected our last goodwill impairment assessment, but no assurance can be provided that the simplified testing methodology will not affect our goodwill impairment assessment in the future. Financial Instruments In June 2016, the FASB issued ASU 2016-13, "Measurement of Credit Losses on Financial Instruments" ("ASU 2016-13"). The primary impact of ASU 2016-13 for us is a change in the model for the recognition of credit losses related to our financial instruments from an incurred loss model, which recognized credit losses only if it was probable that a loss had been incurred, to an expected loss model, which requires our management team to estimate the total credit losses expected on the portfolio of financial instruments. We are currently reviewing the requirements of the standard and evaluating the impact on our consolidated financial statements. We are required to adopt the provisions of ASU 2016-13 effective January 1, 2020, but could elect to early adopt the provisions as of January 1, 2019. We expect to recognize the impacts of adopting ASU 2016-13 through a cumulative adjustment to retained earnings as of the date of adoption. As of the date of this report, we have not yet determined the date we will adopt ASU 2016-13. Leases In February 2016, the FASB issued ASU 2016-02, “Leases” (“ASU 2016-02”). The core principle of ASU 2016-02 will require lessees to present right-of-use assets and lease liabilities on their balance sheets for operating leases, which under GAAP are currently not required to be reflected on their balance sheets. ASU 2016-02 is effective for annual and interim periods beginning January 1, 2019. Upon adoption of ASU 2016-02, we are required to recognize and measure leases at the beginning of the earliest period presented in our consolidated financial statements using a modified retrospective approach. The modified retrospective transition approach includes a number of optional practical expedients that we may elect to apply. In January 2018, the FASB issued ASU 2018-01, “Leases: Land Easement Practical Expedient for Transition to ASU 2016-02" ("ASU 2018-01"). ASU 2018-01 permits reporting companies to elect to forego reassessments of land easements that exist or expire before the entity’s adoption of ASU 2016-02 and that were not previously accounted for as leases. We plan to adopt ASU 2018-01 at the same time we adopt ASU 2016-02. In July 2018, the FASB issued ASU 2018-11, "Leases: Targeted Improvements" ("ASU 2018-11"). ASU 2018-11 provides entities with an additional (and optional) transition method to adopt the new leases standard. Under this new transition method, an entity initially applies the new leases standard at the adoption date and recognizes a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. We have not yet determined whether we will use ASU 2018-11's newly permitted adoption method. We are in the process of implementing a new lease administration and accounting system. We plan to adopt ASU 2016-02 and ASU 2018-01 effective January 1, 2019. The adoption of ASU 2016-02 will result in our recognition of right of use assets and lease liabilities that we have not previously recorded. Although we believe it is premature as of the date of this report to provide any estimate of the impact of adopting ASU 2016-02, we do expect that it will have a material impact on our consolidated financial statements. Additionally, upon implementing ASU 2016-02, accounting for the failed-sale-leaseback transaction described in Note 3—Sale of Data Centers and Colocation Business will no longer be applicable based on our facts and circumstances, and the real estate assets and corresponding financing obligation described therein will be derecognized from our consolidated financial statements.

Acquisition of Level 3 (Tables)

9 Months Ended

Sep. 30, 2018

Business Combinations [Abstract]

Schedule of Business Acquisitions, by Acquisition

As of September 30, 2018, the following is our updated assignment of the preliminary estimated aggregate consideration:



	Adjusted November 1, 2017 Balance as of December 31, 2017			Purchase Price Adjustments ⁽³⁾		Adjusted November 1, 2017 Balance as of September 30, 2018
	(Dollars in millions)
Cash, accounts receivable and other current assets ⁽¹⁾	$	3,317		(25	)	3,292
Property, plant and equipment	9,311			86		9,397
Identifiable intangible assets ⁽²⁾
Customer relationships	8,964			(476	)	8,488
Other	391			(13	)	378
Other noncurrent assets	782			203		985
Current liabilities, excluding current maturities of long-term debt	(1,461		)	(31	)	(1,492	)
Current maturities of long-term debt	(7		)	—		(7	)
Long-term debt	(10,888		)	—		(10,888	)
Deferred revenue and other liabilities	(1,629		)	(102	)	(1,731	)
Goodwill	10,837			353		11,190
Total estimated aggregate consideration	$	19,617		(5	)	19,612

____________________________________________________________________________________________________________


⁽¹⁾	Includes accounts receivable, which had a gross contractual value of $884 million on November 1, 2017 and September 30, 2018.


⁽²⁾	The preliminary estimate of the weighted-average amortization period for the acquired intangible assets is approximately 12.0 years.


⁽³⁾	All purchase price adjustments occurred during the nine months ended September 30, 2018.

Summary of Acquisition Related Expenses

The table below summarizes our acquisition-related expenses, which consist of integration-related expenses, including severance and retention compensation expenses, and transaction-related expenses:



	Three Months Ended September 30,			Nine Months Ended September 30,
	2018		2017	2018	2017
	(Dollars in millions)
Transaction-related expenses	$	1	6	2	23
Integration-related expenses	43		28	275	40
Total acquisition-related expenses	$	44	34	277	63

Summary of Pro Forma Information

The following unaudited pro forma financial information presents the combined results of CenturyLink as if the Level 3 acquisition had been consummated as of January 1, 2017:



	Three Months Ended September 30, 2017		Nine Months Ended September 30, 2017
	(Dollars in millions, except per share amounts)
Operating revenues	$	6,031	18,316
Net income	194		459
Basic earnings per common share	0.18		0.43
Diluted earnings per common share	0.18		0.43

Sale of Data Centers and Colocation Business (Tables)

9 Months Ended

Sep. 30, 2018

Discontinued Operations and Disposal Groups [Abstract]

Schedule of disposal assets held-for-sale and liabilities attributable to disposal assets held-for-sale

The following table reflects the assets sold to and the liabilities assumed by Cyxtera on May 1, 2017, including our estimate of the impact of failed-sale-leaseback:



	Dollars in millions
Goodwill	$	1,142
Property, plant and equipment	1,051
Other intangible assets	249
Other assets	66
Less assets recorded as part of the failed-sale-leaseback	(526		)
Total net amount of assets derecognized	$	1,982

Capital lease obligations	$	294
Other liabilities	274
Less imputed financing obligations from the failed-sale-leaseback	(628		)
Total net imputed liabilities recognized	$	(60	)

- Definition

Tabular disclosure of information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.

+ References

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+ Details

Goodwill, Customer Relationships and Other Intangible Assets Goodwill, Customer Relationships and Other Intangible Assets (Tables)

9 Months Ended

Sep. 30, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Intangible Assets and Goodwill

Goodwill, customer relationships and other intangible assets consisted of the following:



	September 30, 2018		December 31, 2017
	(Dollars in millions)
Goodwill	$	30,770	30,475
Customer relationships, less accumulated amortization of $8,153 and $7,096	$	9,309	10,876
Indefinite-life intangible assets	$	269	269
Other intangible assets subject to amortization:
Capitalized software, less accumulated amortization of $2,547 and $2,294	1,450		1,469
Trade names and patents, less accumulated amortization of $54 and $31	138		159
Total other intangible assets, net	$	1,857	1,897

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense

We estimate that total amortization expense for intangible assets (which include preliminary estimates for the intangible assets acquired from Level 3) for the years ending December 31, 2018 through 2022 will be as follows:



	(Dollars in millions)
2018 (remaining three months)	$	443
2019	1,692
2020	1,589
2021	1,158
2022	982

Schedule of Goodwill

The following table shows the rollforward of goodwill assigned to our reportable segments from December 31, 2017 through September 30, 2018:



	Business			Consumer	Total
	(Dollars in millions)
As of December 31, 2017	$	20,197		10,278	30,475
Purchase accounting and other adjustments	353			—	353
Effect of foreign currency rate change	(58		)	—	(58	)
As of September 30, 2018	$	20,492		10,278	30,770

Revenue Recognition (Tables)

9 Months Ended

Sep. 30, 2018

Revenue from Contract with Customer [Abstract]

Effect of New Accounting Pronouncements

The following tables present our reported results under ASC 606 and a reconciliation to results using the historical accounting method:



	Three Months Ended September 30, 2018
	(Dollars in millions, except per share amounts and shares in thousands)
	Reported Balances as of September 30, 2018		Impact of ASC 606		ASC 605 Historical Adjusted Balances
Operating revenues	$	5,818	(14	)	$	5,804
Cost of services and products (exclusive of depreciation and amortization)	2,672		8		2,680
Selling, general and administrative	967		16		983
Interest expense	557		(7	)	550
Income tax expense	57		(8	)	49
Net income	$	272	(23	)	$	249

BASIC AND DILUTED EARNINGS PER COMMON SHARE
BASIC	$	0.25	(0.02	)	0.23
DILUTED	$	0.25	(0.02	)	0.23
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
BASIC	1,066,904		—		1,066,904
DILUTED	1,072,351		—		1,072,351



	Nine Months Ended September 30, 2018
	(Dollars in millions, except per share amounts and shares in thousands)
	Reported Balances as of September 30, 2018		Impact of ASC 606		ASC 605 Historical Adjusted Balances
Operating revenues	$	17,665	12		$	17,677
Cost of services and products (exclusive of depreciation and amortization)	8,205		18		8,223
Selling, general and administrative	3,191		42		3,233
Interest expense	1,638		(7	)	1,631
Income tax expense	123		(11	)	112
Net income	$	679	(30	)	$	649

BASIC AND DILUTED EARNINGS PER COMMON SHARE
BASIC	$	0.64	(0.03	)	0.61
DILUTED	$	0.63	(0.03	)	0.60
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
BASIC	1,065,410		—		1,065,410
DILUTED	1,069,726		—		1,069,726

The following table presents a reconciliation of certain consolidated balance sheet captions under ASC 606 to the balance sheet results using the historical accounting method:



	As of September 30, 2018
	(Dollars in millions)
	Reported Balances as of September 30, 2018		Impact of ASC 606		ASC 605 Historical Adjusted Balances
Other current assets	$	1,237	(390	)	$	847
Other long-term assets, net	1,014		(93	)	921
Deferred revenue	2,547		(101	)	2,446
Deferred income taxes, net	2,502		(127	)	2,375
Other long-term liabilities	1,075		122		1,197
Retained earnings	777		(377	)	400

Disaggregation of Revenue

The following tables provide disaggregation of revenue from contracts with customers based on service offerings for the three and nine months ended September 30, 2018, respectively. It also shows the amount of revenue that is not subject to ASC 606, but is instead governed by other accounting standards. The adjustment of $43 million noted above was included in the revenue of the consumer segment for the three months ended September 30, 2018; $34 million was recorded to voice and collaboration and $9 million was recorded to transport and infrastructure.



	Three Months Ended September 30, 2018
	(Dollars in millions)
	Total Revenue		Adjustments for Non-ASC 606 Revenue ⁽⁸⁾			Total Revenue from Contracts with Customers
Business segment
IP & Data Services ⁽¹⁾	$	1,726	—			$	1,726
Transport & Infrastructure ⁽²⁾	1,331		(71		)	1,260
Voice & Collaboration ⁽³⁾	1,075		—			1,075
IT & Managed Services ⁽⁴⁾	153		—			153
Total business segment revenues	4,285		(71		)	4,214

Consumer segment
IP & Data Services ⁽⁵⁾	70		(9		)	61
Transport & Infrastructure ⁽⁶⁾	720		(54		)	666
Voice & Collaboration ⁽³⁾	565		—			565
Total consumer segment revenues	1,355		(63		)	1,292

Non-segment revenues
Regulatory revenues ⁽⁷⁾	178		(178		)	—
Total non-segment revenues	178		(178		)	—

Total revenues	$	5,818	$	(312	)	$	5,506

Timing of Revenue
Goods transferred at a point in time						$	51
Services performed over time						5,455
Total revenues from contracts with customers						$	5,506



	Nine Months Ended September 30, 2018
	(Dollars in millions)
	Total Revenue		Adjustments for Non-ASC 606 Revenue ⁽⁸⁾		Total Revenue from Contracts with Customers
Business segment
IP & Data Services ⁽¹⁾	$	5,212	—		$	5,212
Transport & Infrastructure ⁽²⁾	4,021		(217	)	3,804
Voice & Collaboration ⁽³⁾	3,324		—		3,324
IT & Managed Services ⁽⁴⁾	476		—		476
Total business segment revenues	13,033		(217	)	12,816

Consumer segment
IP & Data Services ⁽⁵⁾	249		(25	)	224
Transport & Infrastructure ⁽⁶⁾	2,171		(159	)	2,012
Voice & Collaboration ⁽³⁾	1,666		—		1,666
Total consumer segment revenues	4,086		(184	)	3,902

Non-segment revenues
Regulatory revenues ⁽⁷⁾	546		(546	)	—
Total non-segment revenues	546		(546	)	—

Total revenues	$	17,665	(947	)	$	16,718

Timing of Revenue
Goods transferred at a point in time					$	132
Services performed over time					16,586
Total revenues from contracts with customers					$	16,718



(1	)	Includes primarily VPN data network, Ethernet, IP, video and ancillary revenues.
(2	)	Includes primarily broadband, private line (including business data services), colocation and data centers, wavelength and ancillary revenues.
(3	)	Includes local, long-distance and other ancillary revenues.
(4	)	Includes IT services and managed services revenues.
(5	)	Includes retail video revenues (including our facilities-based video revenues).
(6	)	Includes primarily broadband and equipment sales and professional services revenues.
(7	)	Includes CAF Phase I, CAF Phase 2, federal and state USF support revenue, sublease rental income and failed-sale leaseback income.
(8	)	Includes regulatory revenues, lease revenues, sublease rental income, revenue from fiber capacity lease arrangements and failed sale leaseback income, which are not within the scope of ASC 606.

Contract with Customer, Asset and Liability

The following table provides balances of customer receivables, contract assets and contract liabilities as of September 30, 2018 and January 1, 2018:



	September 30, 2018		January 1, 2018
	(Dollars in millions)
Customer receivables⁽¹⁾	$	2,436	2,504
Contract liabilities	716		623
Contract assets	352		255

⁽¹⁾Gross customer receivables of $2.6 billion and $2.7 billion, net of allowance for doubtful accounts of $153 million and $155 million, at September 30, 2018 and January 1, 2018, respectively.

Capitalized Contract Cost

The following table provides changes in our contract acquisition costs and fulfillment costs:



	Three Months Ended September 30, 2018					Nine Months Ended September 30, 2018
	(Dollars in millions)
	Acquisition Costs			Fulfillment Costs		Acquisition Costs		Fulfillment Costs
Beginning of period balance	$	286		161		268		133
Costs incurred	53			46		152		105
Amortization	(44		)	(34	)	(125	)	(65	)
End of period balance	$	295		173		295		173

Long-Term Debt and Credit Facilities (Tables)

9 Months Ended

Sep. 30, 2018

Debt Disclosure [Abstract]

Schedule of long-term debt including unamortized discounts and premiums

The following chart reflects our consolidated long-term debt, including unamortized discounts and premiums and unamortized debt issuance costs, but excluding intercompany debt:



	Interest Rates⁽¹⁾	Maturities	September 30, 2018			December 31, 2017
			(Dollars in millions)
Senior Secured Debt:
CenturyLink, Inc.
2017 Revolving Credit Facility⁽²⁾	4.898% - 4.908%	2022	$	590		405
Term Loan A	4.992%	2022	1,643			1,575
Term Loan A-1	4.992%	2022	356			370
Term Loan B	4.992%	2025	5,955			6,000
Subsidiaries:
Level 3 Financing, Inc.
Tranche B 2024 Term Loan ⁽³⁾	4.432%	2024	4,611			4,611
Embarq Corporation subsidiaries
First mortgage bonds	7.125% - 8.370%	2023 - 2025	138			151
Senior Notes and Other Debt:
CenturyLink, Inc.
Senior notes	5.625% - 7.650%	2019 - 2042	8,115			8,125
Subsidiaries:
Level 3 Financing, Inc.
Senior notes	5.125% - 6.125%	2021 - 2026	5,315			5,315
Level 3 Parent, LLC
Senior notes	5.125% - 6.1250%	2022	600			600
Qwest Corporation
Senior notes	6.125% - 7.750%	2021 - 2057	5,955			7,294
Term loan	4.250%	2025	100			100
Qwest Capital Funding, Inc.
Senior notes	6.500% - 7.750%	2018 - 2031	979			981
Embarq Corporation and subsidiary
Senior note	7.995%	2036	1,485			1,485
Other	9.000%	2019	150			150
Capital lease and other obligations	Various	Various	825			891
Unamortized premiums and other, net			2			23
Unamortized debt issuance costs			(292		)	(350	)
Total long-term debt			36,527			37,726
Less current maturities			(778		)	(443	)
Long-term debt, excluding current maturities			$	35,749		37,283

______________________________________________________________________


(1)	As ofSeptember 30, 2018.


(2)	The weighed-average interest rate payable on our outstanding revolving line of credit borrowings at December 31, 2017 was 4.186%. The aggregate amount of outstanding revolving line of credit borrowings typically change on a regular basis.


(3)	The Tranche B 2024 Term Loan is a secured obligation and is guaranteed by Level 3 Parent, LLC and certain other subsidiaries. The Tranche B 2024 Term Loan had an interest rate of 4.432% as of September 30, 2018 and 3.557% as of December 31, 2017. The interest rate on the Tranche B 2024 Term Loan is set with a minimum London Interbank Offered Rate ("LIBOR") of zero percent.

Schedule of maturities of long-term debt

Set forth below is the aggregate principal amount of our long-term debt (excluding unamortized discounts, net and unamortized debt issuance costs) maturing during the following years:



	(Dollars in millions)⁽¹⁾⁽²⁾
2018 (remaining three months)	$	241
2019	651
2020	1,202
2021	3,115
2022	5,323
2023 and thereafter	25,785
Total long-term debt	$	36,317

_______________________________________________________________________________

(1)

In Note 3—Sale of Data Centers and Colocation Business, we describe an imputed financing obligation. The amount outstanding on that imputed financing obligation at September 30, 2018 was $568 million. The aggregate maturities of long-term debt do not include $499 million of this obligation, which prior to the end of the lease term on April 30, 2020, will be derecognized along with the remaining net book value of the associated real estate assets.


(2)	Actual principal paid in any year may differ due to the possible future refinancing of outstanding debt or the issuance of new debt. The projected amounts in the table also exclude any impacts from any further acquisitions.

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28541-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 505
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-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21538-112644

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

Severance and Leased Real Estate (Tables)

9 Months Ended

Sep. 30, 2018

Restructuring and Related Activities [Abstract]

Schedule of changes in accrued liabilities for severance expenses and leased real estate

Changes in our accrued liabilities for severance expenses and leased real estate were as follows:



	Severance			Real Estate
	(Dollars in millions)
Balance at December 31, 2017	$	33		64
Accrued to expense	126			60
Payments, net	(137		)	(16	)
Balance at September 30, 2018	$	22		108

Employee Benefits (Tables)

9 Months Ended

Sep. 30, 2018

Retirement Benefits [Abstract]

Schedule of components of net periodic pension benefit (income) expense and post-retirement benefit expense

Net periodic benefit (income) expense for our qualified and non-qualified pension plans included the following components:



	Pension Plans
	Three Months Ended September 30,					Nine Months Ended September 30,
	2018			2017		2018		2017
	(Dollars in millions)
Service cost	$	17		16		49		47
Interest cost	99			102		296		308
Expected return on plan assets	(171		)	(166	)	(513	)	(499	)
Recognition of prior service credit	(2		)	(2	)	(6	)	(6	)
Recognition of actuarial loss	45			51		135		154
Net periodic pension benefit (income) expense	$	(12	)	1		(39	)	4

Net periodic benefit expense for our post-retirement benefit plans included the following components:



	Post-Retirement Benefit Plans
	Three Months Ended September 30,				Nine Months Ended September 30,
	2018			2017	2018		2017
	(Dollars in millions)
Service cost	$	4		4	13		13
Interest cost	24			25	73		75
Expected return on plan assets	(1		)	—	(1	)	(1	)
Recognition of prior service cost	5			5	15		15
Net periodic post-retirement benefit expense	$	32		34	100		102

Earnings Per Common Share (Tables)

9 Months Ended

Sep. 30, 2018

Earnings Per Share [Abstract]

Schedule of basic and diluted earnings per common share

Basic and diluted earnings per common share were calculated as follows:



	Three Months Ended September 30,					Nine Months Ended September 30,
	2018			2017		2018		2017
	(Dollars in millions, except per share amounts, shares in thousands)
Income (Numerator):
Net income	$	272		92		679		272
Earnings applicable to non-vested restricted stock	—			—		—		—
Net income applicable to common stock for computing basic earnings per common share	272			92		679		272
Net income as adjusted for purposes of computing diluted earnings per common share	$	272		92		679		272
Shares (Denominator):
Weighted-average number of shares:
Outstanding during period	1,080,589			549,618		1,077,712		548,779
Non-vested restricted stock	(13,685		)	(8,097	)	(12,302	)	(7,666	)
Weighted-average shares outstanding for computing basic earnings per common share	1,066,904			541,521		1,065,410		541,113
Incremental common shares attributable to dilutive securities:
Shares issuable under convertible securities	10			10		10		10
Shares issuable under incentive compensation plans	5,437			432		4,306		756
Number of shares as adjusted for purposes of computing diluted earnings per common share	1,072,351			541,963		1,069,726		541,879
Basic earnings per common share	$	0.25		0.17		0.64		0.50
Diluted earnings per common share	$	0.25		0.17		0.63		0.50

Fair Value of Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2018

Fair Value Disclosures [Abstract]

Schedule of carrying amounts and estimated fair values of long-term debt, excluding capital lease obligations, and input level to determine fair values

The following table presents the carrying amounts and estimated fair values of our long-term debt, excluding capital lease and other obligations, as well as the input level used to determine the fair values indicated below:



		September 30, 2018			December 31, 2017
	Input Level	Carrying Amount		Fair Value	Carrying Amount	Fair Value
		(Dollars in millions)
Liabilities—Long-term debt, excluding capital lease and other obligations	2	$	35,702	35,750	36,835	36,402

Segment Information (Tables)

9 Months Ended

Sep. 30, 2018

Segment Reporting [Abstract]

Schedule of segment results

The results of our two reportable segments, business and consumer, are summarized below:



	Three Months Ended September 30,					Nine Months Ended September 30,
	2018			2017		2018		2017
	(Dollars in millions)
Total reportable segment revenues	$	5,640		3,845		17,119		11,789
Total reportable segment expenses	2,969			2,197		9,244		6,572
Total reportable segment adjusted EBITDA	$	2,671		1,648		7,875		5,217
Total margin percentage	47		%	43	%	46	%	44	%

Business segment:
Revenues	$	4,285		2,425		13,033		7,485
Expenses	2,446			1,537		7,540		4,641
Adjusted EBITDA	$	1,839		888		5,493		2,844
Margin percentage	43		%	37	%	42	%	38	%
Consumer segment:
Revenues	$	1,355		1,420		4,086		4,304
Expenses	523			660		1,704		1,931
Adjusted EBITDA	$	832		760		2,382		2,373
Margin percentage	61		%	54	%	58	%	55	%

Schedule of operating revenues by products and services

Our operating revenue detail for our products and services consisted of the following categories:



	Three Months Ended September 30,			Nine Months Ended September 30,
	2018		2017	2018	2017
	(Dollars in millions)
Business segment
IP and data services ⁽¹⁾	$	1,726	755	5,212	2,256
Transport and infrastructure ⁽²⁾	1,331		735	4,021	2,426
Voice and collaboration ⁽³⁾	1,075		765	3,324	2,319
IT and managed services ⁽⁴⁾	153		170	476	484
Total business segment revenues	4,285		2,425	13,033	7,485

Consumer segment
IP and data services ⁽⁵⁾	70		98	249	308
Transport and infrastructure ⁽⁶⁾	720		697	2,171	2,063
Voice and collaboration ⁽³⁾	565		625	1,666	1,933
Total consumer segment revenues	1,355		1,420	4,086	4,304

Non-segment revenues
Regulatory revenues ⁽⁷⁾	178		189	546	544
Total non-segment revenues	178		189	546	544

Total revenues	$	5,818	4,034	17,665	12,333

______________________________________________________________________



(1)	Includes primarily VPN data network, Ethernet, IP, video and ancillary revenues.
(2)	Includes primarily broadband, private line (including business data services), colocation and data centers, wavelength and ancillary revenues.
(3)	Includes local, long-distance and other ancillary revenues.
(4)	Includes IT services and managed services revenues.
(5)	Includes retail video revenues (including our facilities-based video revenues).
(6)	Includes primarily broadband and equipment sales and professional services revenues.
(7)	Includes CAF Phase I, CAF Phase 2, federal and state USF support revenue, sublease rental income and failed-sale leaseback income.

Reconciliation of operating profit (loss) from segments to consolidated net income

The following table reconciles total reportable segment adjusted EBITDA to net income:



	Three Months Ended September 30,					Nine Months Ended September 30,
	2018			2017		2018		2017
	(Dollars in millions)
Total reportable segment adjusted EBITDA	$	2,671		1,648		7,875		5,217
Regulatory revenues	178			189		546		544
Depreciation and amortization	(1,285		)	(910	)	(3,858	)	(2,739	)
Other operating expenses	(670		)	(440	)	(2,152	)	(1,537	)
Total other expense, net	(565		)	(348	)	(1,609	)	(999	)
Income before income tax expense	329			139		802		486
Income tax expense	57			47		123		214
Net income	$	272		92		679		272

Other Financial Information (Tables)

9 Months Ended

Sep. 30, 2018

Additional Financial Information Disclosure [Abstract]

Schedule of components of other current assets

The following table presents details of other current assets reflected in our consolidated balance sheets:



	September 30, 2018		December 31, 2017
	(Dollars in millions)
Prepaid expenses	$	379	294
Income tax receivable	79		258
Materials, supplies and inventory	131		128
Contract assets	359		128
Contract acquisition costs	155		—
Other	134		133
Total other current assets	$	1,237	941

Schedule of current liabilities including accounts payable and other current liabilities

The following table presents details of other current liabilities reflected in our consolidated balance sheets:



	September 30, 2018		December 31, 2017
	(Dollars in millions)
Other current liabilities:
Accrued contributions to federal programs	$	136	74
Dividends payable	51		34
Accrued rents	41		14
Accrued rents-telephone poles	35		34
Litigation contingencies	31		45
Other	80		143
Total other current liabilities	$	374	344

Accumulated Other Comprehensive Loss (Tables)

9 Months Ended

Sep. 30, 2018

Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]

Summary of the entity's accumulated other comprehensive income (loss) by component

The tables below summarize changes in accumulated other comprehensive loss recorded on our consolidated balance sheets by component for the nine months ended September 30, 2018:



	Pension Plans			Post-Retirement Benefit Plans		Foreign Currency Translation Adjustment and Other		Total
	(Dollars in millions)
Balance at December 31, 2017	$	(1,731	)	(235	)	(29	)	(1,995	)
Other comprehensive income before reclassifications	—			—		(161	)	(161	)
Amounts reclassified from accumulated other comprehensive income	97			12		—		109
Net current-period other comprehensive income	97			12		(161	)	(52	)
Cumulative effect of adoption of ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income	(375		)	(32	)	—		(407	)
Balance at September 30, 2018	$	(2,009	)	(255	)	(190	)	(2,454	)

The tables below summarize changes in accumulated other comprehensive loss recorded on our consolidated balance sheets by component for the nine months ended September 30, 2017:



	Pension Plans			Post-Retirement Benefit Plans		Foreign Currency Translation Adjustment and Other		Total
	(Dollars in millions)
Balance at December 31, 2016	$	(1,895	)	(162	)	(60	)	(2,117	)
Other comprehensive income before reclassifications	—			—		20		20
Amounts reclassified from accumulated other comprehensive income	93			10		—		103
Net current-period other comprehensive income	93			10		20		123
Balance at September 30, 2017	$	(1,802	)	(152	)	(40	)	(1,994	)

Schedule of reclassifications out of accumulated other comprehensive income (loss) by component

The tables below present further information about our reclassifications out of accumulated other comprehensive loss by component for the three and nine months ended September 30, 2018:



Three Months Ended September 30, 2018	Decrease (Increase) in Net Income			Affected Line Item in Consolidated Statement of Operations
	(Dollars in millions)
Amortization of pension & post-retirement plans⁽¹⁾
Net actuarial loss	$	45		Other income (expense), net
Prior service cost	3			Other income (expense), net
Total before tax	48
Income tax benefit	(11		)	Income tax expense
Net of tax	$	37



Nine Months Ended September 30, 2018	Decrease (Increase) in Net Income			Affected Line Item in Consolidated Statement of Operations
	(Dollars in millions)
Amortization of pension & post-retirement plans⁽¹⁾
Net actuarial loss	$	135		Other income (expense), net
Prior service cost	9			Other income (expense), net
Total before tax	144
Income tax benefit	(35		)	Income tax expense
Net of tax	$	109

________________________________________________________________________


(1)	See Note 8—Employee Benefits for additional information on our net periodic benefit (expense) income related to our pension and post-retirement plans.

The tables below present further information about our reclassifications out of accumulated other comprehensive loss by component for the three and nine months ended September 30, 2017:



Three Months Ended September 30, 2017	Decrease (Increase) in Net Income			Affected Line Item in Consolidated Statement of Operations
	(Dollars in millions)
Amortization of pension & post-retirement plans⁽¹⁾
Net actuarial loss	$	51		Other income (expense), net
Prior service cost	3			Other income (expense), net
Total before tax	54
Income tax benefit	(16		)	Income tax expense
Net of tax	$	38

________________________________________________________________________


(1)	See Note 8—Employee Benefits for additional information on our net periodic benefit (expense) income related to our pension and post-retirement plans.



Nine Months Ended September 30, 2017	Decrease (Increase) in Net Income			Affected Line Item in Consolidated Statement of Operations
	(Dollars in millions)
Amortization of pension & post-retirement plans⁽¹⁾
Net actuarial loss	$	154		Other income (expense), net
Prior service cost	9			Other income (expense), net
Total before tax	163
Income tax benefit	(60		)	Income tax expense
Net of tax	$	103

________________________________________________________________________


(1)	See Note 8—Employee Benefits for additional information on our net periodic benefit (expense) income related to our pension and post-retirement plans.

Background (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended	12 Months Ended
Background (Details) - USD ($) $ in Millions	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Provisional income tax expense (benefit)					$ (1,100)
Purchase accounting adjustment				$ 83
Reduction to provisional benefit				$ 208
Proceeds from income tax refunds	$ 392	$ 314
Cumulative effect of adoption of ASU					(407)
Contract term				30 months
Reclassification from AOCI to retained earnings, tax effect			$ 407
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract term				1 year
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract term				7 years
Business Customer \| Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Length of customer life				12 months
Business Customer \| Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Length of customer life				60 months
Consumer Customers \| Weighted Average
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Length of customer life				30 months
Accounting Standards Update 2014-09 \| RETAINED EARNINGS
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of adoption of ASU		49			346	$ 0	$ 0
Cumulative net effect of adoption, tax		$ 17			$ 117

Acquisition of Level 3 - Additional Information (Details) $ in Millions		3 Months Ended	9 Months Ended	23 Months Ended
	Nov. 01, 2017 USD ($) city dark_fiber	Sep. 30, 2018 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Business Acquisition [Line Items]
Goodwill		$ 30,770	$ 30,770	$ 30,770	$ 30,475
Level 3 Parent, LLC
Business Acquisition [Line Items]
Consideration transferred	$ 19,600
Number of strands of dark fiber divested \| dark_fiber	24
Number of cities connected by dark fiber \| city	30
Goodwill		11,190	11,190	11,190	$ 10,837
Transaction costs and integration-related costs				$ 600
Transaction costs	$ 47
Revenue of acquiree since acquisition date, actual		$ 1,984	$ 6,071

Acquisition of Level 3 - Preliminary Estimated Aggregate Consideration (Details) - USD ($) $ in Millions		9 Months Ended
	Nov. 01, 2017	Sep. 30, 2018	Dec. 31, 2017
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Goodwill		$ 30,770	$ 30,475
Level 3 Parent, LLC
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Cash, accounts receivable and other current assets		3,292	3,317
Property, plant and equipment		9,397	9,311
Other noncurrent assets		985	782
Current liabilities, excluding current maturities of long-term debt		(1,492)	(1,461)
Current maturities of long-term debt		(7)	(7)
Long-term debt		(10,888)	(10,888)
Deferred revenue and other liabilities		(1,731)	(1,629)
Goodwill		11,190	10,837
Total estimated aggregate consideration		19,612	19,617
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments [Abstract]
Cash, accounts receivable and other current assets		(25)
Property, plant and equipment		86
Other noncurrent assets		203
Current liabilities, excluding current maturities of long-term debt		(31)
Current maturities of long-term debt		0
Long-term debt		0
Deferred revenue and other liabilities		(102)
Goodwill		353
Total estimated aggregate consideration		(5)
Accounts receivable contractual value	$ 884	884
Weighted average useful life	12 years
Level 3 Parent, LLC \| Customer relationships
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Identifiable intangible assets		8,488	8,964
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments [Abstract]
Identifiable intangible assets		(476)
Level 3 Parent, LLC \| Other intangible assets
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Identifiable intangible assets		378	$ 391
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments [Abstract]
Identifiable intangible assets		$ (13)

Acquisition of Level 3 - Acquisition Related Expenses (Details) - Level 3 Parent, LLC - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Business Acquisition [Line Items]
Transaction-related expenses	$ 1	$ 6	$ 2	$ 23
Integration-related expenses	43	28	275	40
Total acquisition-related expenses	$ 44	$ 34	$ 277	$ 63

Acquisition of Level 3 - Pro Forma Information (Details) - Level 3 Parent, LLC - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017
Business Acquisition [Line Items]
Operating revenues	$ 6,031	$ 18,316
Net income	$ 194	$ 459
Basic earnings per common share (in dollars per share)	$ 0.18	$ 0.43
Diluted earnings per common share (in dollars per share)	$ 0.18	$ 0.43

Sale of Data Centers and Colocation Business (Details) - USD ($) $ in Millions	May 01, 2017	Sep. 30, 2018	Dec. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total net amount of assets derecognized		$ 19	$ 140
Less imputed financing obligations from the failed-sale-leaseback		(568)
Cyxtera Technologies
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Less assets recorded as part of the failed-sale-leaseback	$ (526)
Less imputed financing obligations from the failed-sale-leaseback	(628)
SIS Holdings, LP
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
CenturyLink, Inc.'s value of minority stake		$ 150
Colocation Business and Data Centers
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from sales of data centers and colocation business	1,800
Colocation Business and Data Centers \| Disposal group disposed of by sale, not discontinued operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill	1,142
Property, plant and equipment	1,051
Other intangible assets	249
Other assets	66
Total net amount of assets derecognized	1,982
Capital lease obligations	294
Other liabilities	274
Total net imputed liabilities recognized	$ (60)

Goodwill, Customer Relationships and Other Intangible Assets - Schedule of Goodwill, Customer Relationships, and Other Intangible Assets (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill	$ 30,770	$ 30,475
Finite-lived intangible assets, net	9,309	10,876
Indefinite-life intangible assets	269	269
Total other intangible assets, net	1,857	1,897
Customer relationships
Goodwill [Line Items]
Finite-lived intangible assets, net	9,309	10,876
Accumulated amortization	(8,153)	(7,096)
Computer Software, Intangible Asset
Goodwill [Line Items]
Finite-lived intangible assets, net	1,450	1,469
Accumulated amortization	(2,547)	(2,294)
Trade Names and Patents
Goodwill [Line Items]
Finite-lived intangible assets, net	138	159
Accumulated amortization	$ (54)	$ (31)

Goodwill, Customer Relationships and Other Intangible Assets - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Goodwill [Line Items]
Intangible assets, net (including goodwill)	$ 19,300		$ 19,300		$ 20,100
Amortization of intangible assets	446	$ 269	1,300	$ 820
Intangible assets, gross (including goodwill)	52,700		52,700
Goodwill	30,770		30,770		30,475
Business
Goodwill [Line Items]
Goodwill	$ 20,492		$ 20,492		$ 20,197

Goodwill, Customer Relationships and Other Intangible Assets - Schedule of Amortization Expense (Details) $ in Millions	Sep. 30, 2018 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2018 (remaining three months)	$ 443
2019	1,692
2020	1,589
2021	1,158
2022	$ 982

Goodwill, Customer Relationships and Other Intangible Assets - Rollforward of Goodwill (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018 USD ($)
Goodwill [Roll Forward]
As of December 31, 2017	$ 30,475
Purchase accounting and other adjustments	353
Effect of foreign currency rate change	(58)
As of September 30, 2018	30,770
Business
Goodwill [Roll Forward]
As of December 31, 2017	20,197
Purchase accounting and other adjustments	353
Effect of foreign currency rate change	(58)
As of September 30, 2018	20,492
Consumer
Goodwill [Roll Forward]
As of December 31, 2017	10,278
Purchase accounting and other adjustments	0
Effect of foreign currency rate change	0
As of September 30, 2018	$ 10,278

Revenue Recognition - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract term				30 months
Revenues	$ 5,818	$ 4,034		$ 17,665	$ 12,333
Contract Fulfillment Costs
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Capitalized contract cost, net	173		$ 161	173		$ 133
Consumer
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	1,355	$ 1,420		4,086	$ 4,304
Restatement Adjustment \| Contract Fulfillment Costs
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Capitalized contract cost, net						$ 45
Accounting Standards Update 2014-09 \| Impact of ASC 606
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	(14)			12
Costs and expenses (less than)	$ 3			$ 3
Accounting Standards Update 2014-09 \| Impact of ASC 606 \| Contract Fulfillment Costs
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Capitalized contract cost, net			45
Accounting Standards Update 2014-09 \| Impact of ASC 606 \| Consumer
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues			43
Accounting Standards Update 2014-09 \| Impact of ASC 606 \| Consumer \| Voice & Collaboration
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues			34
Accounting Standards Update 2014-09 \| Impact of ASC 606 \| Consumer \| Transport & Infrastructure
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues			$ 9
Minimum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract term				1 year
Customer relationship period				10 years
Minimum \| Business Customer
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Length of customer life				12 months
Maximum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract term				7 years
Customer relationship period				20 years
Maximum \| Business Customer
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Length of customer life				60 months
Weighted Average \| Consumer Customers
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Length of customer life				30 months

Revenue Recognition - Reported Results Under ASC 606 (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
OPERATING REVENUES	$ 5,818	$ 4,034	$ 17,665	$ 12,333
Cost of services and products (exclusive of depreciation and amortization)	2,672	1,927	8,205	5,705
Selling, general and administrative	967	710	3,191	2,404
Interest expense	557	362	1,638	1,000
Income tax expense	57	47	123	214
Net income	$ 272	$ 92	$ 679	$ 272
BASIC AND DILUTED EARNINGS PER COMMON SHARE
BASIC (in dollars per share)	$ 0.25	$ 0.17	$ 0.64	$ 0.50
DILUTED (in dollars per share)	$ 0.25	$ 0.17	$ 0.63	$ 0.50
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
BASIC (in shares)	1,066,904	541,521	1,065,410	541,113
DILUTED (in shares)	1,072,351	541,963	1,069,726	541,879
Other current assets	$ 1,237		$ 1,237		$ 941
Other long-term assets, net	1,014		1,014
Deferred revenue	2,547		2,547
Deferred income taxes, net	2,502		2,502		2,413
Other long-term liabilities	1,075		1,075
Retained earnings	777		777		$ 1,103
Impact of ASC 606 \| Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
OPERATING REVENUES	(14)		12
Cost of services and products (exclusive of depreciation and amortization)	8		18
Selling, general and administrative	16		42
Interest expense	(7)		(7)
Income tax expense	(8)		(11)
Net income	$ (23)		$ (30)
BASIC AND DILUTED EARNINGS PER COMMON SHARE
BASIC (in dollars per share)	$ (0.02)		$ (0.03)
DILUTED (in dollars per share)	$ (0.02)		$ (0.03)
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
BASIC (in shares)	0		0
DILUTED (in shares)	0		0
Other current assets	$ (390)		$ (390)
Other long-term assets, net	(93)		(93)
Deferred revenue	(101)		(101)
Deferred income taxes, net	(127)		(127)
Other long-term liabilities	122		122
Retained earnings	(377)		(377)
ASC 605 Historical Adjusted Balances
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
OPERATING REVENUES	5,804		17,677
Cost of services and products (exclusive of depreciation and amortization)	2,680		8,223
Selling, general and administrative	983		3,233
Interest expense	550		1,631
Income tax expense	49		112
Net income	$ 249		$ 649
BASIC AND DILUTED EARNINGS PER COMMON SHARE
BASIC (in dollars per share)	$ 0.23		$ 0.61
DILUTED (in dollars per share)	$ 0.23		$ 0.60
WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING
BASIC (in shares)	1,066,904		1,065,410
DILUTED (in shares)	1,072,351		1,069,726
Other current assets	$ 847		$ 847
Other long-term assets, net	921		921
Deferred revenue	2,446		2,446
Deferred income taxes, net	2,375		2,375
Other long-term liabilities	1,197		1,197
Retained earnings	$ 400		$ 400

Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	$ 5,818	$ 4,034	$ 17,665	$ 12,333
Adjustments	(312)		(947)
Total Revenue from Contracts with Customers	5,506		16,718
Transferred at Point in Time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Revenue from Contracts with Customers	51		132
Transferred over Time
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total Revenue from Contracts with Customers	5,455		16,586
Business
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	4,285	2,425	13,033	7,485
Consumer
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	1,355	1,420	4,086	4,304
Operating segments
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	5,640	3,845	17,119	11,789
Operating segments \| Business
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	4,285	2,425	13,033	7,485
Adjustments	(71)		(217)
Total Revenue from Contracts with Customers	4,214		12,816
Operating segments \| Consumer
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	1,355	1,420	4,086	4,304
Adjustments	(63)		(184)
Total Revenue from Contracts with Customers	1,292		3,902
Operating segments \| IP & Data Services \| Business
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	1,726	755	5,212	2,256
Adjustments	0		0
Total Revenue from Contracts with Customers	1,726		5,212
Operating segments \| IP & Data Services \| Consumer
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	70	98	249	308
Adjustments	(9)		(25)
Total Revenue from Contracts with Customers	61		224
Operating segments \| Transport & Infrastructure \| Business
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	1,331	735	4,021	2,426
Adjustments	(71)		(217)
Total Revenue from Contracts with Customers	1,260		3,804
Operating segments \| Transport & Infrastructure \| Consumer
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	720	697	2,171	2,063
Adjustments	(54)		(159)
Total Revenue from Contracts with Customers	666		2,012
Operating segments \| Voice & Collaboration \| Business
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	1,075	765	3,324	2,319
Adjustments	0		0
Total Revenue from Contracts with Customers	1,075		3,324
Operating segments \| Voice & Collaboration \| Consumer
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	565	625	1,666	1,933
Adjustments	0		0
Total Revenue from Contracts with Customers	565		1,666
Operating segments \| IT & Managed Services \| Business
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	153	170	476	484
Adjustments	0		0
Total Revenue from Contracts with Customers	153		476
Corporate, Non-Segment
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	178	189	546	544
Adjustments	(178)		(546)
Total Revenue from Contracts with Customers	0		0
Corporate, Non-Segment \| Regulatory Revenue
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	178	$ 189	546	$ 544
Adjustments	(178)		(546)
Total Revenue from Contracts with Customers	$ 0		$ 0

Revenue Recognition - Contract with Customer, Asset and Liability (Details) - USD ($) $ in Millions	Sep. 30, 2018	Jan. 01, 2018
Revenue from Contract with Customer [Abstract]
Customer receivables	$ 2,436	$ 2,504
Contract liabilities	716	623
Contract assets	352	255
Accounts receivable, gross	2,600	2,700
Allowance for doubtful accounts receivable	$ 153	$ 155

Revenue Recognition - Remaining Performance Obligation (Details) $ in Billions	Sep. 30, 2018 USD ($)
Revenue from Contract with Customer [Abstract]
Remaining performance obligation	$ 9.2
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, percentage	73.00%
Remaining performance obligation, satisfaction period	2 years 3 months

Revenue Recognition - Capitalized Contract Costs (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018
Contract Acquisition Costs
Capitalized Contract Cost [Roll Forward]
Beginning of period balance	$ 286	$ 268
Costs incurred	53	152
Amortization	(44)	(125)
End of period balance	295	295
Contract Fulfillment Costs
Capitalized Contract Cost [Roll Forward]
Beginning of period balance	161	133
Costs incurred	46	105
Amortization	(34)	(65)
End of period balance	$ 173	$ 173

Long-Term Debt and Credit Facilities - Schedule of Long Term Debt (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Long-term Debt and Credit Facilities
Capital lease and other obligations	$ 825	$ 891
Unamortized premiums and other, net	2	23
Unamortized debt issuance costs	(292)	(350)
Total long-term debt	36,527	37,726
Less current maturities	(778)	(443)
Long-term debt, excluding current maturities	35,749	$ 37,283
CenturyLink, Inc. \| Line of credit
Long-term Debt and Credit Facilities
Long-term debt, weighted average interest rate		4.186%
CenturyLink, Inc. \| Line of credit \| New Revolving Credit Facility
Long-term Debt and Credit Facilities
Long-term debt, gross	$ 590	$ 405
CenturyLink, Inc. \| Line of credit \| New Revolving Credit Facility \| Minimum
Long-term Debt and Credit Facilities
Stated interest rate	4.898%
CenturyLink, Inc. \| Line of credit \| New Revolving Credit Facility \| Maximum
Long-term Debt and Credit Facilities
Stated interest rate	4.908%
CenturyLink, Inc. \| Medium-term notes \| Term Loan A
Long-term Debt and Credit Facilities
Stated interest rate	4.99219%
Long-term debt, gross	$ 1,643	1,575
CenturyLink, Inc. \| Medium-term notes \| Term Loan A-1
Long-term Debt and Credit Facilities
Stated interest rate	4.99219%
Long-term debt, gross	$ 356	370
CenturyLink, Inc. \| Medium-term notes \| Term Loan B
Long-term Debt and Credit Facilities
Stated interest rate	4.99219%
Long-term debt, gross	$ 5,955	6,000
CenturyLink, Inc. \| Senior notes
Long-term Debt and Credit Facilities
Long-term debt, gross	$ 8,115	$ 8,125
CenturyLink, Inc. \| Senior notes \| Minimum
Long-term Debt and Credit Facilities
Stated interest rate	5.625%
CenturyLink, Inc. \| Senior notes \| Maximum
Long-term Debt and Credit Facilities
Stated interest rate	7.65%
Level 3 Financing, Inc. \| Medium-term notes
Long-term Debt and Credit Facilities
Stated interest rate	4.432%	3.557%
Long-term debt, gross	$ 4,611	$ 4,611
Level 3 Financing, Inc. \| Medium-term notes \| Minimum
Long-term Debt and Credit Facilities
Basis spread on variable rate	0.00%
Level 3 Financing, Inc. \| Senior notes
Long-term Debt and Credit Facilities
Long-term debt, gross	$ 5,315	5,315
Level 3 Financing, Inc. \| Senior notes \| Minimum
Long-term Debt and Credit Facilities
Stated interest rate	5.125%
Level 3 Financing, Inc. \| Senior notes \| Maximum
Long-term Debt and Credit Facilities
Stated interest rate	6.125%
Embarq Corporation \| First mortgage bonds
Long-term Debt and Credit Facilities
Long-term debt, gross	$ 138	151
Embarq Corporation \| First mortgage bonds \| Minimum
Long-term Debt and Credit Facilities
Stated interest rate	7.125%
Embarq Corporation \| First mortgage bonds \| Maximum
Long-term Debt and Credit Facilities
Stated interest rate	8.37%
Embarq Corporation \| Senior notes
Long-term Debt and Credit Facilities
Stated interest rate	7.995%
Long-term debt, gross	$ 1,485	1,485
Embarq Corporation \| Other
Long-term Debt and Credit Facilities
Stated interest rate	9.00%
Long-term debt, gross	$ 150	150
Level 3 Parent, LLC \| Senior notes
Long-term Debt and Credit Facilities
Long-term debt, gross	$ 600	600
Level 3 Parent, LLC \| Senior notes \| Minimum
Long-term Debt and Credit Facilities
Stated interest rate	5.125%
Level 3 Parent, LLC \| Senior notes \| Maximum
Long-term Debt and Credit Facilities
Stated interest rate	6.125%
Qwest Corporation \| Medium-term notes
Long-term Debt and Credit Facilities
Stated interest rate	4.25%
Long-term debt, gross	$ 100	100
Qwest Corporation \| Senior notes
Long-term Debt and Credit Facilities
Long-term debt, gross	$ 5,955	7,294
Qwest Corporation \| Senior notes \| Minimum
Long-term Debt and Credit Facilities
Stated interest rate	6.125%
Qwest Corporation \| Senior notes \| Maximum
Long-term Debt and Credit Facilities
Stated interest rate	7.75%
Qwest Capital Funding, Inc. \| Senior notes
Long-term Debt and Credit Facilities
Long-term debt, gross	$ 979	$ 981
Qwest Capital Funding, Inc. \| Senior notes \| Minimum
Long-term Debt and Credit Facilities
Stated interest rate	6.50%
Qwest Capital Funding, Inc. \| Senior notes \| Maximum
Long-term Debt and Credit Facilities
Stated interest rate	7.75%

Long-Term Debt and Credit Facilities - Schedule of Maturities of Long Term Debt (Details) $ in Millions	Sep. 30, 2018 USD ($)
Long-term Debt, Fiscal Year Maturity
2018 and remaining	$ 241
2019	651
2020	1,202
2021	3,115
2022	5,323
2023 and thereafter	25,785
Total long-term debt	36,317
Capital lease obligations	568
Excluded from maturity of long term debt	$ 499

Long-Term Debt and Credit Facilities - Additional Information (Details) $ in Millions	3 Months Ended
	Sep. 30, 2018 USD ($)
Long-term Debt and Credit Facilities
Repayments of debt	$ 1,300
Senior notes \| Qwest Notes Due 2051
Long-term Debt and Credit Facilities
Repayments of debt	$ 164
Stated interest rate	7.50%
Senior notes \| Qwest Notes due 2052
Long-term Debt and Credit Facilities
Repayments of debt	$ 925
Stated interest rate	7.00%
Senior notes \| Qwest Notes 2035
Long-term Debt and Credit Facilities
Repayments of debt	$ 250
Stated interest rate	7.25%

Severance and Leased Real Estate (Details) $ in Millions	9 Months Ended
Severance and Leased Real Estate (Details) $ in Millions	Sep. 30, 2018 USD ($)
Employee severance
Restructuring reserve
Balance at the beginning of the period	$ 33
Accrued to expense	126
Payments, net	(137)
Balance at the end of the period	22
Leased real estate
Leased Real Estate
Current portion of leased real estate accrual	21
Noncurrent portion of leased real estate accrual	87
Restructuring reserve
Balance at the beginning of the period	64
Accrued to expense	60
Payments, net	(16)
Balance at the end of the period	$ 108
Minimum \| Leased real estate
Leased Real Estate
Lease term	3 months 5 days
Maximum \| Leased real estate
Leased Real Estate
Lease term	12 years 3 months 19 days
Weighted Average \| Leased real estate
Leased Real Estate
Lease term	7 years 2 days

Employee Benefits (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Employee Benefits (Details) - USD ($) $ in Millions	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Pension plans
Components of net periodic (benefit) expense
Service cost	$ 17	$ 16	$ 49	$ 47
Interest cost	99	102	296	308
Expected return on plan assets	(171)	(166)	(513)	(499)
Recognition of prior service credit	(2)	(2)	(6)	(6)
Recognition of actuarial loss	45	51	135	154
Net periodic pension benefit (income) expense	(12)	1	(39)	4
Voluntary contributions to plan by employer	400		500
Post-retirement benefit plans
Components of net periodic (benefit) expense
Service cost	4	4	13	13
Interest cost	24	25	73	75
Expected return on plan assets	(1)	0	(1)	(1)
Recognition of prior service credit	5	5	15	15
Net periodic pension benefit (income) expense	$ 32	$ 34	$ 100	$ 102

Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income (Numerator):
Net income	$ 272	$ 92	$ 679	$ 272
Weighted-average number of shares:
Weighted average shares outstanding for computing basic earnings per common share (in shares)	1,066,904	541,521	1,065,410	541,113
Incremental common shares attributable to dilutive securities:
Number of shares as adjusted for purposes of computing diluted earnings per common share (in shares)	1,072,351	541,963	1,069,726	541,879
Basic earnings per common share (in dollars per share)	$ 0.25	$ 0.17	$ 0.64	$ 0.50
Diluted earnings per common share (in dollars per share)	$ 0.25	$ 0.17	$ 0.63	$ 0.50
Common Class A
Income (Numerator):
Net income	$ 272	$ 92	$ 679	$ 272
Earnings applicable to non-vested restricted stock	0	0	0	0
Net income applicable to common stock for computing basic earnings per common share	272	92	679	272
Net income as adjusted for purposes of computing diluted earnings per common share	$ 272	$ 92	$ 679	$ 272
Weighted-average number of shares:
Outstanding during period (in shares)	1,080,589	549,618	1,077,712	548,779
Non-vested restricted stock (in shares)	(13,685)	(8,097)	(12,302)	(7,666)
Weighted average shares outstanding for computing basic earnings per common share (in shares)	1,066,904	541,521	1,065,410	541,113
Incremental common shares attributable to dilutive securities:
Shares issuable under convertible securities (in shares)	10	10	10	10
Shares issuable under incentive compensation plans (in shares)	5,437	432	4,306	756
Number of shares as adjusted for purposes of computing diluted earnings per common share (in shares)	1,072,351	541,963	1,069,726	541,879
Basic earnings per common share (in dollars per share)	$ 0.25	$ 0.17	$ 0.64	$ 0.50
Diluted earnings per common share (in dollars per share)	$ 0.25	$ 0.17	$ 0.63	$ 0.50
Number of shares of common stock excluded from the computation of diluted earnings per share (in shares)	1,500	5,100	3,000	4,200

Fair Value of Financial Instruments (Details) - Fair value measurements determined on a nonrecurring basis - Fair value inputs, Level 2 - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Carrying amount
Liabilities
Liabilities—Long-term debt, excluding capital lease and other obligations	$ 35,702	$ 36,835
Fair value
Liabilities
Liabilities—Long-term debt, excluding capital lease and other obligations	$ 35,750	$ 36,402

Segment Information - Results (Details) $ in Millions		3 Months Ended		9 Months Ended
Segment Information - Results (Details) $ in Millions	Nov. 01, 2017 segment	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) category segment	Sep. 30, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	2			2
Revenues		$ 5,818	$ 4,034	$ 17,665	$ 12,333
Expenses		4,924	3,547	15,254	10,848
OPERATING INCOME		894	487	$ 2,411	1,485
Number of categories of products and services \| category				5
Business
Segment Reporting Information [Line Items]
Revenues		4,285	2,425	$ 13,033	7,485
Expenses		2,446	1,537	7,540	4,641
OPERATING INCOME		$ 1,839	$ 888	$ 5,493	$ 2,844
Margin percentage		43.00%	37.00%	42.00%	38.00%
Consumer
Segment Reporting Information [Line Items]
Revenues		$ 1,355	$ 1,420	$ 4,086	$ 4,304
Expenses		523	660	1,704	1,931
OPERATING INCOME		$ 832	$ 760	$ 2,382	$ 2,373
Margin percentage		61.00%	54.00%	58.00%	55.00%
Operating segments
Segment Reporting Information [Line Items]
Revenues		$ 5,640	$ 3,845	$ 17,119	$ 11,789
Expenses		2,969	2,197	9,244	6,572
OPERATING INCOME		$ 2,671	$ 1,648	$ 7,875	$ 5,217
Margin percentage		47.00%	43.00%	46.00%	44.00%
Operating segments \| Business
Segment Reporting Information [Line Items]
Revenues		$ 4,285	$ 2,425	$ 13,033	$ 7,485
Operating segments \| Consumer
Segment Reporting Information [Line Items]
Revenues		$ 1,355	$ 1,420	$ 4,086	$ 4,304

Segment Information - Operating Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Operating revenues by products and services
Revenues	$ 5,818	$ 4,034	$ 17,665	$ 12,333
Surcharge amount on customers' bills	221	129	698	392
Business
Operating revenues by products and services
Revenues	4,285	2,425	13,033	7,485
Consumer
Operating revenues by products and services
Revenues	1,355	1,420	4,086	4,304
Operating segments
Operating revenues by products and services
Revenues	5,640	3,845	17,119	11,789
Operating segments \| Business
Operating revenues by products and services
Revenues	4,285	2,425	13,033	7,485
Operating segments \| Business \| IP & Data Services
Operating revenues by products and services
Revenues	1,726	755	5,212	2,256
Operating segments \| Business \| Transport & Infrastructure
Operating revenues by products and services
Revenues	1,331	735	4,021	2,426
Operating segments \| Business \| Voice & Collaboration
Operating revenues by products and services
Revenues	1,075	765	3,324	2,319
Operating segments \| Business \| IT & Managed Services
Operating revenues by products and services
Revenues	153	170	476	484
Operating segments \| Consumer
Operating revenues by products and services
Revenues	1,355	1,420	4,086	4,304
Operating segments \| Consumer \| IP & Data Services
Operating revenues by products and services
Revenues	70	98	249	308
Operating segments \| Consumer \| Transport & Infrastructure
Operating revenues by products and services
Revenues	720	697	2,171	2,063
Operating segments \| Consumer \| Voice & Collaboration
Operating revenues by products and services
Revenues	565	625	1,666	1,933
Corporate, Non-Segment
Operating revenues by products and services
Revenues	178	189	546	544
Corporate, Non-Segment \| Regulatory Revenue
Operating revenues by products and services
Revenues	$ 178	$ 189	$ 546	$ 544

Segment Information - Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Depreciation and amortization	$ (1,285)	$ (910)	$ (3,858)	$ (2,739)
Total other expense, net	(565)	(348)	(1,609)	(999)
Income before income tax expense	329	139	802	486
Income tax expense	57	47	123	214
NET INCOME	272	92	679	272
Operating segments
Segment Reporting Information [Line Items]
Total reportable segment adjusted EBITDA	2,671	1,648	7,875	5,217
Segment Reconciling Items
Segment Reporting Information [Line Items]
Regulatory revenues	178	189	546	544
Depreciation and amortization	(1,285)	(910)	(3,858)	(2,739)
Other operating expenses	(670)	(440)	(2,152)	(1,537)
Total other expense, net	$ (565)	$ (348)	$ (1,609)	$ (999)

Commitments and Contingencies and Other Items (Details) $ in Millions	1 Months Ended	6 Months Ended	9 Months Ended
	Feb. 28, 2017 USD ($) lawsuit	Sep. 30, 2018 USD ($) lawsuit	Sep. 30, 2018 USD ($) lawsuit	Dec. 31, 2017 USD ($)	Dec. 31, 2005 USD ($)
Loss Contingencies
Estimate of possible loss		$ 138	$ 138
New claims filed, number \| lawsuit		6
Letters of credit outstanding, amount		$ 129	$ 129	$ 104
Patents allegedly infringed \| lawsuit			1
Louisiana State Court
Loss Contingencies
New claims filed, number \| lawsuit		2
Louisiana Federal Court
Loss Contingencies
New claims filed, number \| lawsuit		4
Level 3 Parent, LLC
Loss Contingencies
Loss contingency, damages sought, value			$ 50
Level 3 Parent, LLC \| Pending litigation \| Peruvian Tax Litigation, Before Interest
Loss Contingencies
Loss contingency, asserted claim					$ 26
Level 3 Parent, LLC \| Pending litigation \| Peruvian Tax Litigation
Loss Contingencies
Loss contingency, asserted claim		$ 13	13
Level 3 Parent, LLC \| Pending litigation \| Employee Severance and Contractor Termination Disputes
Loss Contingencies
Loss contingency, asserted claim		30	30
Level 3 Parent, LLC \| Pending litigation \| Brazilian Tax Claims \| Maximum
Loss Contingencies
Loss contingency, range of possible loss, portion not accrued		$ 34	$ 34
Interexchange Carriers \| CenturyLink, Inc.
Loss Contingencies
Number of lawsuits \| lawsuit		100	100
Missouri municipalities \| Judicial ruling
Loss Contingencies
Number of cases, final court order \| lawsuit	1
Litigation settlement amount	$ 4

Other Financial Information (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Prepaid Expenses and Other Current Assets [Abstract]
Prepaid expenses	$ 379	$ 294
Income tax receivable	79	258
Materials, supplies and inventory	131	128
Contract assets	359	128
Contract acquisition costs	155	0
Other	134	133
Total other current assets	1,237	941
Other Current Liabilities
Accrued contributions to federal programs	136	74
Dividends payable	51	34
Accrued rents	41	14
Accrued rents-telephone poles	35	34
Litigation contingencies	31	45
Other	80	143
Total other current liabilities	374	344
Accounts Payable, Current [Abstract]
Book overdraft balance	$ 58	$ 36

Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Accumulated other comprehensive loss
Balance at beginning of period			$ 23,491
Other comprehensive income (loss) before reclassifications			(161)	$ 20
Amounts reclassified from accumulated other comprehensive income			109	103
Other comprehensive income (loss)	$ 36	$ 56	(52)	123
Cumulative effect of adoption of ASU					$ (407)
Balance at end of period	22,803	12,960	22,803	12,960
Defined benefit plan \| Pension plans
Accumulated other comprehensive loss
Balance at beginning of period			(1,731)	(1,895)
Other comprehensive income (loss) before reclassifications			0	0
Amounts reclassified from accumulated other comprehensive income			97	93
Other comprehensive income (loss)			97	93
Cumulative effect of adoption of ASU					(375)
Balance at end of period	(2,009)	(1,802)	(2,009)	(1,802)
Defined benefit plan \| Post-retirement benefit plans
Accumulated other comprehensive loss
Balance at beginning of period			(235)	(162)
Other comprehensive income (loss) before reclassifications			0	0
Amounts reclassified from accumulated other comprehensive income			12	10
Other comprehensive income (loss)			12	10
Cumulative effect of adoption of ASU					(32)
Balance at end of period	(255)	(152)	(255)	(152)
Foreign currency translation adjustment and other
Accumulated other comprehensive loss
Balance at beginning of period			(29)	(60)
Other comprehensive income (loss) before reclassifications			(161)	20
Amounts reclassified from accumulated other comprehensive income			0	0
Other comprehensive income (loss)			(161)	20
Cumulative effect of adoption of ASU					$ 0
Balance at end of period	(190)	(40)	(190)	(40)
Accumulated other comprehensive income
Accumulated other comprehensive loss
Balance at beginning of period	(2,490)	(2,050)	(1,995)	(2,117)
Other comprehensive income (loss)	36	56	(52)	123
Balance at end of period	$ (2,454)	$ (1,994)	$ (2,454)	$ (1,994)

Accumulated Other Comprehensive Loss - Reclassifications (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Reclassifications out of accumulated other comprehensive income loss by component
Other income (expense), net	$ 25	$ 14	$ 63	$ 6
Total before tax	329	139	802	486
Income tax expense	(57)	(47)	(123)	(214)
NET INCOME	272	92	679	272
Reclassification out of Accumulated Other Comprehensive Income \| Net actuarial loss
Reclassifications out of accumulated other comprehensive income loss by component
Other income (expense), net	45	51	135	154
Reclassification out of Accumulated Other Comprehensive Income \| Prior service cost
Reclassifications out of accumulated other comprehensive income loss by component
Other income (expense), net	3	3	9	9
Reclassification out of Accumulated Other Comprehensive Income \| Defined benefit plan
Reclassifications out of accumulated other comprehensive income loss by component
Total before tax	48	54	144	163
Income tax expense	(11)	(16)	(35)	(60)
NET INCOME	$ 37	$ 38	$ 109	$ 103

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Labor Union Contracts (Details)	9 Months Ended
Labor Union Contracts (Details)	Sep. 30, 2018
Concentration risk
Number of unionized employees (less than)	300
Total number of employees \| Unionized employees concentration risk
Concentration risk
Concentration risk, percent	26.00%
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year \| Unionized employees concentration risk
Concentration risk
Concentration risk, percent	1.00%