Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2018	Oct. 17, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q3
Entity Registrant Name	AMAZON COM INC
Entity Central Index Key	0001018724
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Smaller Reporting Company	false
Entity Common Stock, Shares Outstanding		488,968,628

Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Cash Flows [Abstract]
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, BEGINNING OF PERIOD	$ 20,536	$ 13,851	$ 21,856	$ 19,934	$ 13,960	$ 14,124
OPERATING ACTIVITIES:
Net income	2,883	256	7,046	1,176	8,902	1,926
Adjustments to reconcile net income to net cash from operating activities:
Depreciation of property and equipment, including internal-use software and website development, and other amortization, including capitalized content costs	3,778	2,912	11,079	7,980	14,577	10,277
Stock-based compensation	1,350	1,085	4,001	3,036	5,180	3,923
Other operating expense, net	62	43	202	146	258	177
Other expense (income), net	96	(128)	22	(288)	17	(267)
Deferred income taxes	266	(74)	268	279	(40)	(2)
Changes in operating assets and liabilities:
Inventories	(1,094)	(1,593)	36	(1,328)	(2,220)	(2,371)
Accounts receivable, net and other	(2,884)	(1,760)	(3,220)	(2,016)	(5,983)	(3,938)
Accounts payable	3,894	2,974	(3,618)	(1,803)	5,285	5,479
Accrued expenses and other	237	(122)	(2,193)	(1,778)	(131)	476
Unearned revenue	0	184	623	603	759	1,316
Net cash provided by (used in) operating activities	8,588	3,777	14,246	6,007	26,604	16,996
INVESTING ACTIVITIES:
Purchases of property and equipment, including internal-use software and website development	3,352	3,074	9,693	8,336	13,312	10,750
Proceeds from property and equipment incentives	825	415	1,490	1,314	2,073	1,723
Acquisitions, net of cash acquired, and other	(976)	(13,213)	(1,855)	(13,891)	(1,936)	(13,893)
Sales and maturities of marketable securities	1,964	2,211	6,301	6,191	9,787	7,384
Purchases of marketable securities	(4,033)	(4,817)	(5,040)	(10,381)	(7,390)	(13,633)
Net cash provided by (used in) investing activities	(5,572)	(18,478)	(8,797)	(25,103)	(10,778)	(29,169)
FINANCING ACTIVITIES:
Proceeds from long-term debt and other	143	16,049	363	16,119	472	16,653
Repayments of long-term debt and other	(183)	(71)	(533)	(159)	(1,675)	(217)
Principal repayments of capital lease obligations	(2,247)	(1,267)	(5,544)	(3,327)	(7,016)	(4,331)
Principal repayments of finance lease obligations	(82)	(49)	(211)	(134)	(277)	(175)
Net cash provided by (used in) financing activities	(2,369)	14,662	(5,925)	12,499	(8,496)	11,930
Foreign currency effect on cash, cash equivalents, and restricted cash	(151)	148	(348)	623	(258)	79
Net increase (decrease) in cash, cash equivalents, and restricted cash	496	109	(824)	(5,974)	7,072	(164)
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, END OF PERIOD	21,032	13,960	21,032	13,960	21,032	13,960
SUPPLEMENTAL CASH FLOW INFORMATION:
Cash paid for interest on long-term debt	283	5	733	155	907	299
Cash paid for interest on capital and finance lease obligations	165	112	419	235	503	296
Cash paid for income taxes, net of refunds	200	172	1,013	865	1,106	960
Property and equipment acquired under capital leases	2,329	2,256	6,934	6,867	9,704	8,905
Property and equipment acquired under build-to-suit leases	$ 962	$ 750	$ 2,498	$ 2,698	$ 3,340	$ 3,114

Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Total net sales	$ 56,576	$ 43,744	$ 160,504	$ 117,413
Operating expenses:
Cost of sales	33,003	27,549	94,370	73,439
Fulfillment	8,275	6,420	23,999	16,275
Marketing	3,303	2,479	8,902	6,629
Technology and content	7,162	5,944	21,168	16,306
General and administrative	1,041	960	3,219	2,630
Other operating expense, net	68	45	211	155
Total operating expenses	52,852	43,397	151,869	115,434
Operating income	3,724	347	8,635	1,979
Interest income	117	54	290	137
Interest expense	(358)	(228)	(1,030)	(510)
Other income (expense), net	(93)	143	16	329
Total non-operating income (expense)	(334)	(31)	(724)	(44)
Income before income taxes	3,390	316	7,911	1,935
Provision for income taxes	(508)	(58)	(870)	(755)
Equity-method investment activity, net of tax	1	(2)	5	(4)
Net income	$ 2,883	$ 256	$ 7,046	$ 1,176
Basic earnings per share	$ 5.91	$ 0.53	$ 14.49	$ 2.46
Diluted earnings per share	$ 5.75	$ 0.52	$ 14.10	$ 2.39
Weighted-average shares used in computation of earnings per share:
Basic (in shares)	488	481	486	479
Diluted (in shares)	501	494	500	492
Product [Member]
Total net sales	$ 33,746	$ 28,768	$ 97,215	$ 77,248
Service [Member]
Total net sales	$ 22,830	$ 14,976	$ 63,289	$ 40,165

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	$ 2,883	$ 256	$ 7,046	$ 1,176
Other comprehensive income (loss):
Foreign currency translation adjustments, net of tax of $10, $2, $(5), and $19	(101)	104	(512)	486
Net change in unrealized gains (losses) on available-for-sale debt securities:
Unrealized gains (losses), net of tax of $(1), $0, $1, and $8	0	(2)	(43)	(10)
Reclassification adjustment for losses (gains) included in “Other income (expense), net,” net of tax of $0, $0, $0, and $0	1	3	5	8
Net unrealized gains (losses) on available-for-sale debt securities	1	1	(38)	(2)
Total other comprehensive income (loss)	(100)	105	(550)	484
Comprehensive income	$ 2,783	$ 361	$ 6,496	$ 1,660

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]
Foreign currency translation adjustments, tax	$ (2)	$ 10	$ 19	$ (5)
Unrealized gains (losses), tax	0	(1)	8	1
Reclassification adjustment for losses (gains) included in “Other income (expense), net,” tax	$ 0	$ 0	$ 0	$ 0

Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 20,425	$ 20,522
Marketable securities	9,340	10,464
Inventories	15,862	16,047
Accounts receivable, net and other	14,258	13,164
Total current assets	59,885	60,197
Property and equipment, net	58,019	48,866
Goodwill	14,553	13,350
Other assets	11,238	8,897
Total assets	143,695	131,310
Current liabilities:
Accounts payable	30,904	34,616
Accrued expenses and other	18,420	18,170
Unearned revenue	6,000	5,097
Total current liabilities	55,324	57,883
Long-term debt	24,684	24,743
Other long-term liabilities	24,562	20,975
Commitments and contingencies (Note 3)
Stockholders’ equity:
Preferred stock, $0.01 par value: Authorized shares - 500 Issued and outstanding shares - none	0	0
Common stock, $0.01 par value: Authorized shares - 5,000 Issued shares - 507 and 512 Outstanding shares - 484 and 489	5	5
Treasury stock, at cost	(1,837)	(1,837)
Additional paid-in capital	25,375	21,389
Accumulated other comprehensive loss	(1,034)	(484)
Retained earnings	16,616	8,636
Total stockholders’ equity	39,125	27,709
Total liabilities and stockholders’ equity	$ 143,695	$ 131,310

Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Preferred stock, par value (in usd per share)	$ 0.01	$ 0.01
Preferred stock, authorized shares	500,000,000	500,000,000
Preferred stock, issued shares	0	0
Preferred stock, outstanding shares	0	0
Common stock, par value (in usd per share)	$ 0.01	$ 0.01
Common stock, authorized shares	5,000,000,000	5,000,000,000
Common stock, issued shares	512,000,000	507,000,000
Common stock, outstanding shares	489,000,000	484,000,000

Accounting Policies

9 Months Ended

Sep. 30, 2018

Accounting Policies [Abstract]

Accounting Policies

ACCOUNTING POLICIES

Unaudited Interim Financial Information

We have prepared the accompanying consolidated financial statements pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”) for interim financial reporting. These consolidated financial statements are unaudited and, in our opinion, include all adjustments, consisting of normal recurring adjustments and accruals necessary for a fair presentation of our consolidated balance sheets, operating results, and cash flows for the periods presented. Operating results for the periods presented are not necessarily indicative of the results that may be expected for 2018 due to seasonal and other factors. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) have been omitted in accordance with the rules and regulations of the SEC. These consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes in Item 8 of Part II, “Financial Statements and Supplementary Data,” of our 2017 Annual Report on Form 10-K.

Prior Period Reclassifications

Certain prior period amounts have been reclassified to conform to the current period presentation, including the addition of restricted cash to cash and cash equivalents on the consolidated statements of cash flows as a result of the adoption of new accounting guidance.

Principles of Consolidation

The consolidated financial statements include the accounts of Amazon.com, Inc., its wholly-owned subsidiaries, and those entities in which we have a variable interest and of which we are the primary beneficiary, including certain entities in India and China and that support our seller lending financing activities (collectively, the “Company”). Intercompany balances and transactions between consolidated entities are eliminated. The financial results of Whole Foods Market, Inc. (“Whole Foods Market”) have been included in our consolidated financial statements from the date of acquisition on August 28, 2017.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires estimates and assumptions that affect the reported amounts of assets and liabilities, revenues and expenses, and related disclosures of contingent liabilities in the consolidated financial statements and accompanying notes. Estimates are used for, but not limited to, income taxes, commitments and contingencies, valuation of acquired intangibles and goodwill, stock-based compensation forfeiture rates, vendor funding, and inventory valuation. Actual results could differ materially from those estimates.

Earnings per Share

Basic earnings per share is calculated using our weighted-average outstanding common shares. Diluted earnings per share is calculated using our weighted-average outstanding common shares including the dilutive effect of stock awards as determined under the treasury stock method. In periods when we have a net loss, stock awards are excluded from our calculation of earnings per share as their inclusion would have an antidilutive effect.

The following table shows the calculation of diluted shares (in millions):



	Three Months Ended September 30,		Nine Months Ended September 30,
	2017	2018	2017	2018
Shares used in computation of basic earnings per share	481	488	479	486
Total dilutive effect of outstanding stock awards	13	13	13	14
Shares used in computation of diluted earnings per share	494	501	492	500

Revenue

Revenue is measured based on the amount of consideration that we expect to receive, reduced by estimates for return allowances, promotional discounts, and rebates. Revenue also excludes any amounts collected on behalf of third parties, including sales and indirect taxes. In arrangements where we have multiple performance obligations, the transaction price is allocated to each performance obligation using the relative stand-alone selling price. We generally determine stand-alone selling prices based on the prices charged to customers or using expected cost plus a margin.

A description of our principal revenue generating activities is as follows:

Retail sales - We offer consumer products through our online and physical stores. Revenue is recognized when control of the goods is transferred to the customer, which generally occurs upon our delivery to a third-party carrier or, in the case of an Amazon delivery, to the customer.

Third-party seller services - We offer programs that enable sellers to sell their products on our websites and their own branded websites, and fulfill orders through us. We are not the seller of record in these transactions. The commissions and any related fulfillment and shipping fees we earn from these arrangements are recognized when the services are rendered, which generally occurs upon delivery of the related products to a third-party carrier or, in the case of an Amazon delivery, to the customer.

Subscription services - Our subscription sales include fees associated with Amazon Prime memberships and access to content including audiobooks, digital video, e-books, digital music, and other non-AWS subscription services. Prime memberships provide our customers with access to an evolving suite of benefits that represent a single stand-ready obligation. Subscriptions are paid for at the time of or in advance of delivering the services. Revenue from such arrangements is recognized over the subscription period.

AWS - Our AWS arrangements include global sales of compute, storage, database, and other services. Revenue is allocated to services using stand-alone selling prices and is primarily recognized when the customer uses these services, based on the quantity of services rendered, such as compute or storage capacity delivered on-demand. Certain services, including compute and database, are also offered as a fixed quantity over a specified term, for which revenue is recognized ratably. Sales commissions we pay in connection with contracts that exceed one year are capitalized and amortized over the contract term.

Other - Other revenue primarily includes sales of advertising services, which are recognized as ads are delivered based on the number of clicks or impressions.

Return Allowances

Return allowances, which reduce revenue and cost of sales, are estimated using historical experience. Liabilities for return allowances are included in “Accrued expenses and other” and were $468 million and $407 million as of December 31, 2017 and September 30, 2018. Included in “Inventories” on our consolidated balance sheets are assets totaling $406 million and $310 million as of December 31, 2017 and September 30, 2018, for the rights to recover products from customers associated with our liabilities for return allowances.

Cost of Sales

Cost of sales primarily consists of the purchase price of consumer products, digital media content costs where we recognize revenue gross, including video and music, packaging supplies, sortation and delivery centers and related equipment costs, and inbound and outbound shipping costs, including where we are the transportation service provider. Shipping costs to receive products from our suppliers are included in our inventory, and recognized as cost of sales upon sale of products to our customers. Payment processing and related transaction costs, including those associated with seller transactions, are classified in “Fulfillment” on our consolidated statements of operations.

Vendor Agreements

We have agreements with our vendors to receive funds primarily for cooperative marketing efforts, promotions, incentives, and volume rebates. We generally consider these amounts received from vendors to be a reduction of the prices we pay for their goods, including property and equipment, or services, and are recorded as a reduction of the cost of inventory, cost of services, or cost of property and equipment. Volume rebates typically depend on reaching minimum purchase thresholds. We evaluate the likelihood of reaching purchase thresholds using past experience and current year forecasts. When volume rebates can be reasonably estimated, we record a portion of the rebate as we make progress towards the purchase threshold.

Accounts Receivable, Net and Other

Included in “Accounts receivable, net and other” on our consolidated balance sheets are amounts primarily related to customers, vendors, and sellers. As of December 31, 2017 and September 30, 2018, customer receivables, net, were $6.4 billion and $8.4 billion, vendor receivables, net, were $2.6 billion and $2.1 billion, and seller receivables, net, were $692 million and $689 million. Seller receivables are amounts due from sellers related to our seller lending program, which provides funding to sellers primarily to procure inventory.

We estimate losses on receivables based on known troubled accounts and historical experience of losses incurred. Receivables are considered impaired and written-off when it is probable that all contractual payments due will not be collected in accordance with the terms of the agreement. The allowance for doubtful accounts was $348 million and $457 million as of December 31, 2017 and September 30, 2018.

Unearned Revenue

Unearned revenue is recorded when payments are received or due in advance of performing our service obligations and is recognized over the service period. Unearned revenue primarily relates to prepayments of Amazon Prime memberships and AWS services. Our total unearned revenue as of December 31, 2017 was $6.1 billion, of which $4.9 billion was recognized as revenue during the nine months ended September 30, 2018, including adjustments related to the new revenue recognition guidance. Included in “Other long-term liabilities” on our consolidated balance sheets was $1.0 billion and $1.2 billion of unearned revenue as of December 31, 2017 and September 30, 2018.

Additionally, we have performance obligations, primarily related to AWS, associated with commitments in customer contracts for future services that have not yet been recognized in our financial statements. For contracts with original terms that exceed one year, the amount of revenue not yet recognized was $17.8 billion as of September 30, 2018. The weighted average remaining life of our long-term contracts is 3.5 years. However, the timing of revenue recognition is largely driven by customer usage, which can extend beyond the original contractual term.

Accrued Expenses and Other

Included in “Accrued expenses and other” on our consolidated balance sheets are amounts primarily related to unredeemed gift cards, customer liabilities, leases and asset retirement obligations, current debt, acquired digital media content, and other operating expenses.

As of December 31, 2017 and September 30, 2018, our liabilities for unredeemed gift cards were $3.0 billion and $1.7 billion. We reduce the liability for a gift card when redeemed by a customer. The portion of gift cards that we do not expect to be redeemed is recognized based on customer usage patterns.

Accounting Pronouncements Recently Adopted

In May 2014, the FASB issued an Accounting Standards Update (“ASU”) amending revenue recognition guidance and requiring more detailed disclosures to enable users of financial statements to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. We adopted this ASU on January 1, 2018 for all revenue contracts with our customers using the modified retrospective approach and increased retained earnings by approximately $650 million. The adjustment primarily relates to the unredeemed portion of our gift cards, which are now recognized over the expected customer usage period rather than waiting until gift cards expire or when the likelihood of redemption becomes remote. We changed the recognition and classification of Amazon Prime memberships, which are now accounted for as a single performance obligation and recognized ratably over the membership period as service sales. Previously, Prime memberships were considered to be arrangements with multiple deliverables and were allocated among product sales and service sales. Other changes relate primarily to the presentation of revenue. Certain advertising services are now classified as revenue rather than a reduction in cost of sales, and sales of apps, in-app content, and certain digital media content are presented on a net basis.

The impact of applying this ASU for the nine months ended September 30, 2018 primarily resulted in a decrease in product sales and an increase in service sales driven by the reclassification of Prime membership fees of approximately $2.6 billion. Service sales also increased by approximately $2.0 billion for the nine months ended September 30, 2018 due to the reclassification of certain advertising services.

In January 2016, the FASB issued an ASU that updates certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. Under this ASU, certain equity investments are measured at fair value with changes recognized in net income. We adopted this ASU in Q1 2018 with no material impact to our consolidated financial statements.

In October 2016, the FASB issued an ASU amending the accounting for income taxes. The new guidance requires the recognition of the income tax consequences of an intercompany asset transfer, other than transfers of inventory, when the transfer occurs. For intercompany transfers of inventory, the income tax effects will continue to be deferred until the inventory has been sold to a third party. We adopted this ASU in Q1 2018 with an increase of approximately $250 million to retained earnings and deferred tax assets net of valuation allowances.

In November 2016, the FASB issued an ASU amending the presentation of restricted cash within the consolidated statements of cash flows. The new guidance requires that restricted cash be added to cash and cash equivalents on the consolidated statements of cash flows. We adopted this ASU in Q1 2018 on a retrospective basis with the following impacts to our consolidated statements of cash flows (in millions):



Three Months Ended September 30, 2017	Previously Reported			Adjustments			As Revised
Operating activities	$	3,851		$	(74	)	$	3,777
Investing activities	(19,120		)	642			(18,478		)
Financing activities	14,685			(23		)	14,662
Net change in cash, cash equivalents, and restricted cash	$	(584	)	$	545		$	(39	)



Nine Months Ended September 30, 2017	Previously Reported			Adjustments			As Revised
Operating activities	$	6,090		$	(83	)	$	6,007
Investing activities	(25,787		)	684			(25,103		)
Financing activities	12,507			(8		)	12,499
Net change in cash, cash equivalents, and restricted cash	$	(7,190	)	$	593		$	(6,597	)



Twelve Months Ended September 30, 2017	Previously Reported			Adjustments			As Revised
Operating activities	$	17,077		$	(81	)	$	16,996
Investing activities	(29,961		)	792			(29,169		)
Financing activities	11,916			14			11,930
Net change in cash, cash equivalents, and restricted cash	$	(968	)	$	725		$	(243	)

Accounting Pronouncements Not Yet Adopted

In February 2016, the FASB issued an ASU amending the accounting for leases. The new guidance requires the recognition of lease assets and liabilities for operating leases with terms of more than 12 months, in addition to those currently recorded, on our consolidated balance sheets. Presentation of leases within the consolidated statements of operations and consolidated statements of cash flows will be generally consistent with the current lease accounting guidance. The ASU is effective for reporting periods beginning after December 15, 2018, with early adoption permitted. We will adopt this ASU on January 1, 2019 with a cumulative adjustment to retained earnings rather than retrospectively adjusting prior periods. This adoption approach will result in a balance sheet presentation that is not comparable to the prior period in the first year of adoption. To illustrate the magnitude of this change, the amount of our off-balance sheet operating leases at September 30, 2018 is disclosed in “Note 3 — Commitments and Contingencies.” Beginning on January 1, 2019, our operating leases, excluding those with terms less than 12 months, will be discounted and recorded as assets and liabilities on our consolidated balance sheet.

Cash, Cash Equivalents, and Marketable Securities

9 Months Ended

Sep. 30, 2018

Investments, Debt and Equity Securities [Abstract]

Cash, Cash Equivalents, and Marketable Securities

CASH, CASH EQUIVALENTS, RESTRICTED CASH, AND MARKETABLE SECURITIES

As of December 31, 2017 and September 30, 2018, our cash, cash equivalents, restricted cash, and marketable securities primarily consisted of cash, U.S. and foreign government and agency securities, AAA-rated money market funds, and other investment grade securities. Cash equivalents and marketable securities are recorded at fair value. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. To increase the comparability of fair value measures, the following hierarchy prioritizes the inputs to valuation methodologies used to measure fair value:

Level 1—Valuations based on quoted prices for identical assets and liabilities in active markets.

Level 2—Valuations based on observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets, quoted prices for identical or similar assets and liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data.

Level 3—Valuations based on unobservable inputs reflecting our own assumptions, consistent with reasonably available assumptions made by other market participants. These valuations require significant judgment.

We measure the fair value of money market funds and equity securities based on quoted prices in active markets for identical assets or liabilities. All other financial instruments were valued either based on recent trades of securities in inactive markets or based on quoted market prices of similar instruments and other significant inputs derived from or corroborated by observable market data. We did not hold any cash, cash equivalents, restricted cash, or marketable securities categorized as Level 3 assets as of December 31, 2017 and September 30, 2018.

The following table summarizes, by major security type, our cash, cash equivalents, restricted cash, and marketable securities that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy (in millions):



	December 31, 2017			September 30, 2018
	Total Estimated Fair Value			Cost or Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Total Estimated Fair Value
Cash	$	9,982		$	8,053	$	—	$	—		$	8,053
Level 1 securities:
Money market funds	11,343			11,128		—		—			11,128
Equity securities	53			28		137		—			165
Level 2 securities:
Foreign government and agency securities	620			481		—		—			481
U.S. government and agency securities	4,823			5,544		1		(26		)	5,519
Corporate debt securities	4,257			4,006		1		(17		)	3,990
Asset-backed securities	905			826		—		(5		)	821
Other fixed income securities	338			189		—		(3		)	186
Equity securities	—			28		3		—			31
	$	32,321		$	30,283	$	142	$	(51	)	$	30,374
Less: Restricted cash, cash equivalents, and marketable securities (1)	(1,335		)								(609		)
Total cash, cash equivalents, and marketable securities	$	30,986									$	29,765

___________________

(1)

We are required to pledge or otherwise restrict a portion of our cash, cash equivalents, and marketable securities as collateral for real estate leases, amounts due to third-party sellers in certain jurisdictions, debt, and standby and trade letters of credit. We classify cash, cash equivalents, and marketable securities with use restrictions of less than twelve months as “Accounts receivable, net and other” and of twelve months or longer as non-current “Other assets” on our consolidated balance sheets. See “Note 3 — Commitments and Contingencies.”

The following table summarizes the remaining contractual maturities of our cash equivalents and marketable fixed income securities as of September 30, 2018 (in millions):



	Amortized Cost		Estimated Fair Value
Due within one year	$	18,390	$	18,380
Due after one year through five years	3,079		3,053
Due after five years through ten years	224		221
Due after ten years	481		471
Total	$	22,174	$	22,125

Actual maturities may differ from the contractual maturities because borrowers may have certain prepayment conditions.

We also hold equity warrant assets giving us the right to acquire stock of other companies. As of December 31, 2017 and September 30, 2018, these warrants had a fair value of $441 million and $573 million, and are recorded within “Other assets” on our consolidated balance sheets. The related gain (loss) recorded in “Other income (expense), net” was $76 million and $(62) million in Q3 2017 and Q3 2018, and $145 million and $25 million for the nine months ended September 30, 2017 and 2018. These assets are primarily classified as Level 2 assets.

The following table provides a reconciliation of the amount of cash, cash equivalents, and restricted cash reported within the consolidated balance sheets to the total of the same such amounts shown in the consolidated statements of cash flows (in millions):



	December 31, 2017		September 30, 2018
Cash and cash equivalents	$	20,522	$	20,425
Restricted cash included in accounts receivable, net and other	1,329		604
Restricted cash included in other assets	5		3
Total cash, cash equivalents, and restricted cash shown in the consolidated statements of cash flows	$	21,856	$	21,032

Commitments and Contingencies

9 Months Ended

Sep. 30, 2018

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

COMMITMENTS AND CONTINGENCIES

Commitments

We have entered into non-cancellable operating, capital, and finance leases for equipment and office, fulfillment, sortation, delivery, data center, physical store, and renewable energy facilities. Rental expense under operating lease agreements was $553 million and $859 million for Q3 2017 and Q3 2018, and $1.4 billion and $2.5 billion for the nine months ended September 30, 2017 and 2018.

The following summarizes our principal contractual commitments, excluding open orders for purchases that support normal operations and are generally cancellable, as of September 30, 2018 (in millions):



	Three Months Ended December 31,		Year Ended December 31,
	2018		2019		2020		2021		2022		Thereafter		Total
Debt principal and interest	$	213	$	2,186	$	2,111	$	1,833	$	2,049	$	31,769	$	40,161
Capital lease obligations, including interest (1)	1,363		6,912		4,753		1,740		583		773		16,124
Finance lease obligations, including interest (2)	145		609		625		636		647		5,654		8,316
Operating leases	748		2,902		2,752		2,468		2,200		13,453		24,523
Unconditional purchase obligations (3)	137		3,760		3,488		3,265		3,054		8,096		21,800
Other commitments (4) (5)	841		1,734		1,157		1,184		649		7,936		13,501
Total commitments	$	3,447	$	18,103	$	14,886	$	11,126	$	9,182	$	67,681	$	124,425

___________________


(1)	Excluding interest, current capital lease obligations of $5.8 billion and $6.9 billion are recorded within “Accrued expenses and other” as of December 31, 2017 and September 30, 2018, and $8.4 billion and $8.7 billion are recorded within “Other long-term liabilities” as of December 31, 2017 and September 30, 2018.


(2)	Excluding interest, current finance lease obligations of $282 million and $391 million are recorded within “Accrued expenses and other” as of December 31, 2017 and September 30, 2018, and $4.7 billion and $6.5 billion are recorded within “Other long-term liabilities” as of December 31, 2017 and September 30, 2018.

(3)

Includes unconditional purchase obligations related to certain products offered in our Whole Foods Market stores and long-term agreements to acquire and license digital media content that are not reflected on the consolidated balance sheets. For those digital media content agreements with variable terms, we do not estimate the total obligation beyond any minimum quantities and/or pricing as of the reporting date. Purchase obligations associated with renewal provisions solely at the option of the content provider are included to the extent such commitments are fixed or a minimum amount is specified.


(4)	Includes the estimated timing and amounts of payments for rent and tenant improvements associated with build-to-suit lease arrangements and equipment lease arrangements that have not been placed in service and digital media content liabilities associated with long-term digital media content assets with initial terms greater than one year.


(5)	Excludes approximately $3.4 billion of accrued tax contingencies for which we cannot make a reasonably reliable estimate of the amount and period of payment, if any.

Pledged Assets

As of December 31, 2017 and September 30, 2018, we have pledged or otherwise restricted $1.4 billion and $688 million of our cash, cash equivalents, and marketable securities, and certain property and equipment as collateral for real estate leases, amounts due to third-party sellers in certain jurisdictions, debt, and standby and trade letters of credit.

Other Contingencies

In 2016, we determined that we processed and delivered orders of consumer products for certain individuals and entities located outside Iran covered by the Iran Threat Reduction and Syria Human Rights Act or other United States sanctions and export control laws. The consumer products included books, music, other media, apparel, home and kitchen, health and beauty, jewelry, office, consumer electronics, software, lawn and patio, grocery, and automotive products. Our review is ongoing and we have voluntarily reported these orders to the United States Treasury Department’s Office of Foreign Assets Control and the United States Department of Commerce’s Bureau of Industry and Security. We intend to cooperate fully with OFAC and BIS with respect to their review, which may result in the imposition of penalties. For additional information, see Item 5 of Part II, “Other Information — Disclosure Pursuant to Section 13(r) of the Exchange Act.”

We are subject to claims related to various indirect taxes (such as sales, value added, consumption, service, and similar taxes), including in jurisdictions in which we already collect and remit such taxes. If the relevant taxing authorities were successfully to pursue these claims, we could be subject to significant additional tax liabilities. For example, in June 2017, the State of South Carolina issued an assessment for uncollected sales and use taxes for the period from January 2016 to March 2016, including interest and penalties. South Carolina is alleging that we should have collected sales and use taxes on transactions by our third-party sellers. We believe the assessment is without merit. If South Carolina or other states were successfully to seek additional adjustments of a similar nature, we could be subject to significant additional tax liabilities. We intend to defend ourselves vigorously in this matter.

Legal Proceedings

The Company is involved from time to time in claims, proceedings, and litigation, including the matters described in Item 8 of Part II, “Financial Statements and Supplementary Data — Note 7 — Commitments and Contingencies — Legal Proceedings” of our 2017 Annual Report on Form 10-K and in Item 1 of Part I, “Financial Statements — Note 3 — Commitments and Contingencies — Legal Proceedings” of our Quarterly Reports on Form 10-Q for the periods ended March 31, 2018 and June 30, 2018.

The outcomes of our legal proceedings and other contingencies are inherently unpredictable, subject to significant uncertainties, and could be material to our operating results and cash flows for a particular period. In addition, for the matters we disclose that do not include an estimate of the amount of loss or range of losses, such an estimate is not possible or is immaterial, and we may be unable to estimate the possible loss or range of losses that could potentially result from the application of non-monetary remedies.

See also “Note 7 — Income Taxes.”

Acquisitions, Goodwill, and Acquired Intangible Assets

9 Months Ended

Sep. 30, 2018

Business Combinations [Abstract]

Acquisitions, Goodwill, and Acquired Intangible Assets

ACQUISITIONS, GOODWILL, AND ACQUIRED INTANGIBLE ASSETS

2018 Acquisition Activity

On April 12, 2018, we acquired Ring Inc. (“Ring”) for cash consideration of approximately $839 million, net of cash acquired, and on September 11, 2018, we acquired PillPack, Inc. (“PillPack”) for cash consideration of approximately $753 million, net of cash acquired, to expand our product and service offerings. During the nine months ended September 30, 2018, we also acquired certain other companies for an aggregate purchase price of $46 million. The primary reason for our other 2018 acquisitions was to acquire technologies and know-how to enable Amazon to serve customers more effectively.

Acquisition-related costs were expensed as incurred and were not significant. Due to the limited amount of time since the PillPack acquisition, the valuation of certain assets and liabilities is preliminary and subject to change. The aggregate purchase price of Ring, PillPack, and the other 2018 acquisitions was allocated as follows (in millions):



Purchase Price
Cash paid, net of cash acquired	$	1,609
Indemnification holdback	29
	$	1,638

Allocation
Goodwill	$	1,222
Intangible assets (1):
Marketing-related	186
Contract-based	13
Technology-based	279
Customer-related	193
	671
Property and equipment	11
Deferred tax assets	174
Other assets acquired	282
Long-term debt	(176		)
Deferred tax liabilities	(159		)
Other liabilities assumed	(387		)
	$	1,638

___________________


(1)	Acquired intangible assets have estimated useful lives of between two and seven years, with a weighted-average amortization period of six years.

We determined the estimated fair value of identifiable intangible assets acquired primarily by using the income approach. These assets are included within “Other assets” on our consolidated balance sheets and are being amortized to operating expenses on a straight-line basis over their estimated useful lives.

Pro forma results of operations have not been presented because the effects of these acquisitions, individually and in the aggregate, were not material to our consolidated results of operations.

Goodwill

The goodwill of the acquired companies is primarily related to expected improvements in technology performance and functionality, as well as sales growth from future product and service offerings and new customers, together with certain intangible assets that do not qualify for separate recognition. The goodwill of acquired companies is generally not deductible for tax purposes. The following summarizes our goodwill activity in the first nine months of 2018 by segment (in millions):



	North America			International			AWS			Consolidated
Goodwill - December 31, 2017	$	11,165		$	1,108		$	1,077		$	13,350
New acquisitions (1)	1,030			177			15			1,222
Other adjustments (2)	(2		)	(10		)	(7		)	(19		)
Goodwill - September 30, 2018	$	12,193		$	1,275		$	1,085		$	14,553

___________________


(1)	Primarily includes the acquisitions of Ring and PillPack in the North America and International segments.


(2)	Primarily includes changes in foreign exchange rates.

Long-Term Debt

9 Months Ended

Sep. 30, 2018

Debt Disclosure [Abstract]

Long-Term Debt

DEBT

As of September 30, 2018, we had $24.3 billion of unsecured senior notes outstanding (the “Notes”). As of December 31, 2017 and September 30, 2018, the net unamortized discount and debt issuance costs on the Notes was $99 million and $101 million. We also have other long-term debt with a carrying amount, including the current portion and borrowings under our credit facility, of $692 million and $579 million as of December 31, 2017 and September 30, 2018. The face value of our total long-term debt obligations is as follows (in millions):



	December 31, 2017			September 30, 2018
2.600% Notes due on December 5, 2019 (2)	1,000			1,000
1.900% Notes due on August 21, 2020 (3)	1,000			1,000
3.300% Notes due on December 5, 2021 (2)	1,000			1,000
2.500% Notes due on November 29, 2022 (1)	1,250			1,250
2.400% Notes due on February 22, 2023 (3)	1,000			1,000
2.800% Notes due on August 22, 2024 (3)	2,000			2,000
3.800% Notes due on December 5, 2024 (2)	1,250			1,250
5.200% Notes due on December 3, 2025 (4)	1,000			1,000
3.150% Notes due on August 22, 2027 (3)	3,500			3,500
4.800% Notes due on December 5, 2034 (2)	1,250			1,250
3.875% Notes due on August 22, 2037 (3)	2,750			2,750
4.950% Notes due on December 5, 2044 (2)	1,500			1,500
4.050% Notes due on August 22, 2047 (3)	3,500			3,500
4.250% Notes due on August 22, 2057 (3)	2,250			2,250
Credit Facility	592			535
Other long-term debt	100			44
Total debt	24,942			24,829
Less current portion of long-term debt	(100		)	(44		)
Face value of long-term debt	$	24,842		$	24,785

_____________________________


(1)	Issued in November 2012, effective interest rate of the 2022 Notes was 2.66%.


(2)	Issued in December 2014, effective interest rates of the 2019, 2021, 2024, 2034, and 2044 Notes were 2.73%, 3.43%, 3.90%, 4.92%, and 5.11%.


(3)	Issued in August 2017, effective interest rates of the 2020, 2023, 2024, 2027, 2037, 2047, and 2057 Notes were 2.16%, 2.56%, 2.95%, 3.25%, 3.94%, 4.13%, and 4.33%.


(4)	Consists of $872 million of 2025 Notes issued in December 2017 in exchange for notes assumed in connection with the acquisition of Whole Foods Market and $128 million of 2025 Notes issued by Whole Foods Market that did not participate in our December 2017 exchange offer. The effective interest rate of the 2025 Notes was 3.02%.

Interest on the Notes issued in 2012 is payable semi-annually in arrears in May and November. Interest on the Notes issued in 2014 is payable semi-annually in arrears in June and December. Interest on the Notes issued in 2017 is payable semi-annually in arrears in February and August. Interest on the 2025 Notes is payable semi-annually in arrears in June and December. We may redeem the Notes at any time in whole, or from time to time, in part at specified redemption prices. We are not subject to any financial covenants under the Notes. The proceeds from the November 2012 and the December 2014 Notes were used for general corporate purposes. The proceeds from the August 2017 Notes were used to fund the consideration for the acquisition of Whole Foods Market, to repay notes due in 2017, and for general corporate purposes. The estimated fair value of the Notes was approximately $25.7 billion and $24.2 billion as of December 31, 2017 and September 30, 2018, which is based on quoted prices for our debt as of those dates.

In October 2016, we entered into a $500 million secured revolving credit facility with a lender that is secured by certain seller receivables, which we subsequently increased to $600 million and may from time to time increase in the future subject to lender approval (the “Credit Facility”). The Credit Facility is available for a term of three years, bears interest at the London interbank offered rate (“LIBOR”) plus 1.65%, and has a commitment fee of 0.50% on the undrawn portion. There were $592 million and $535 million of borrowings outstanding under the Credit Facility as of December 31, 2017 and September 30, 2018, with weighted-average interest rates of 2.7% and 3.0% as of December 31, 2017 and September 30, 2018. As of December 31, 2017 and September 30, 2018, we have pledged $686 million and $620 million of our cash and seller receivables as collateral for debt related to our Credit Facility. The estimated fair value of the Credit Facility, which is based on Level 2 inputs, approximated its carrying value as of December 31, 2017 and September 30, 2018.

The other debt, including the current portion, had a weighted-average interest rate of 5.8% and 7.3% as of December 31, 2017 and September 30, 2018. We used the net proceeds from the issuance of this debt primarily to fund certain business operations. The estimated fair value of the other long-term debt, which is based on Level 2 inputs, approximated its carrying value as of December 31, 2017 and September 30, 2018.

In April 2018, we established a commercial paper program (the “Commercial Paper Program”) under which we may from time to time issue unsecured commercial paper up to a total of $7.0 billion at any time, with individual maturities that may vary but will not exceed 397 days from the date of issue. There were no borrowings outstanding under the Commercial Paper Program as of September 30, 2018.

In April 2018, in connection with our Commercial Paper Program, we amended and restated our unsecured revolving credit facility (the “Credit Agreement”) with a syndicate of lenders to increase our borrowing capacity thereunder to $7.0 billion. As amended and restated, the Credit Agreement has a term of three years, but it may be extended for up to three additional one-year terms if approved by the lenders. The interest rate applicable to outstanding balances under the amended and restated Credit Agreement is LIBOR plus 0.50%, with a commitment fee of 0.04% on the undrawn portion of the credit facility. There were no borrowings outstanding under the Credit Agreement as of December 31, 2017 and September 30, 2018.

Stockholders' Equity

9 Months Ended

Sep. 30, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stockholders' Equity

STOCKHOLDERS’ EQUITY

Stock Repurchase Activity

In February 2016, the Board of Directors authorized a program to repurchase up to $5.0 billion of our common stock, with no fixed expiration. There were no repurchases of common stock during the nine months ended September 30, 2017 or 2018.

Stock Award Activity

Common shares outstanding plus shares underlying outstanding stock awards totaled 504 million and 507 million as of December 31, 2017 and September 30, 2018. These totals include all vested and unvested stock awards outstanding, including those awards we estimate will be forfeited. Stock-based compensation expense is as follows (in millions):



	Three Months Ended September 30,				Nine Months Ended September 30,
	2017		2018		2017		2018
Cost of sales	$	13	$	19	$	33	$	52
Fulfillment	230		269		655		834
Marketing	135		201		363		552
Technology and content	595		719		1,668		2,138
General and administrative	112		142		317		426
Total stock-based compensation expense	$	1,085	$	1,350	$	3,036	$	4,002

The following table summarizes our restricted stock unit activity for the nine months ended September 30, 2018 (in millions):



	Number of Units		Weighted-Average Grant-Date Fair Value
Outstanding as of December 31, 2017	20.1		$	725
Units granted	4.4		1,512
Units vested	(4.8	)	551
Units forfeited	(1.7	)	831
Outstanding as of September 30, 2018	18.0		$	954

Scheduled vesting for outstanding restricted stock units as of September 30, 2018, is as follows (in millions):



	Three Months Ended December 31,	Year Ended December 31,
	2018	2019	2020	2021	2022	Thereafter	Total
Scheduled vesting—restricted stock units	2.3	7.0	5.6	2.3	0.6	0.2	18.0

As of September 30, 2018, there was $7.3 billion of net unrecognized compensation cost related to unvested stock-based compensation arrangements. This compensation is recognized on an accelerated basis with approximately half of the compensation expected to be expensed in the next twelve months, and has a weighted-average recognition period of 1.1 years. The estimated forfeiture rate as of December 31, 2017 and September 30, 2018 was 28% and 27%. Changes in our estimates and assumptions relating to forfeitures may cause us to realize material changes in stock-based compensation expense in the future.

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES Our tax provision or benefit from income taxes for interim periods is determined using an estimate of our annual effective tax rate, adjusted for discrete items, if any, that are taken into account in the relevant period. Each quarter we update our estimate of the annual effective tax rate, and if our estimated tax rate changes, we make a cumulative adjustment. Our quarterly tax provision, and our quarterly estimate of our annual effective tax rate, is subject to significant variation due to several factors, including variability in accurately predicting our pre-tax and taxable income and loss and the mix of jurisdictions to which they relate, intercompany transactions, the applicability of special tax regimes, changes in how we do business, acquisitions (including integrations) and investments, audit-related developments, changes in our stock price, changes in our deferred tax assets and liabilities and their valuation, foreign currency gains (losses), changes in statutes, regulations, case law, and administrative practices, principles, and interpretations related to tax, accounting, and other areas, including European Union state aid rules, and relative changes of expenses or losses for which tax benefits are not recognized. Additionally, our effective tax rate can be more or less volatile based on the amount of pre-tax income or loss. For example, the impact of discrete items and non-deductible expenses on our effective tax rate is greater when our pre-tax income is lower. The 2017 Tax Act was signed into law on December 22, 2017. The 2017 Tax Act significantly revised the U.S. corporate income tax by, among other things, lowering the statutory corporate tax rate from 35% to 21%, eliminating certain deductions, imposing a mandatory one-time tax on accumulated earnings of foreign subsidiaries, introducing new tax regimes, and changing how foreign earnings are subject to U.S. tax. The 2017 Tax Act also enhanced and extended through 2026 the option to claim accelerated depreciation deductions on qualified property. We have not completed our determination of the accounting implications of the 2017 Tax Act on our tax accruals. However, we reasonably estimated the effects of the 2017 Tax Act and recorded provisional amounts in our financial statements as of December 31, 2017. We recorded a provisional tax benefit for the impact of the 2017 Tax Act of approximately $789 million. This amount was primarily comprised of the remeasurement of federal net deferred tax liabilities resulting from the permanent reduction in the U.S. statutory corporate tax rate to 21% from 35%, after taking into account the mandatory one-time tax on the accumulated earnings of our foreign subsidiaries. The amount of this one-time tax is not material. As we complete our analysis of the 2017 Tax Act, collect and prepare necessary data, and interpret any additional guidance issued by the U.S. Treasury Department, the IRS, and other standard-setting bodies, we may make adjustments to the provisional amounts. Those adjustments may materially impact our provision for income taxes in the period in which the adjustments are made. For 2018, we estimate that our effective tax rate will be favorably affected by the impact of excess tax benefits from stock-based compensation and the U.S. federal research and development credit and adversely affected by state income taxes and losses incurred in certain foreign jurisdictions for which we may not realize a tax benefit. Losses for which we may not realize a related tax benefit, primarily due to losses of foreign subsidiaries, reduce our pre-tax income without a corresponding reduction in our tax expense, and therefore increase our effective tax rate. We record valuation allowances against the deferred tax assets associated with losses for which we may not realize a related tax benefit. Our income tax provision for the nine months ended September 30, 2017 was $755 million, which included $422 million of net discrete tax benefits primarily attributable to excess tax benefits from stock-based compensation, partially offset by the estimated impact of audit-related developments. Our income tax provision for the nine months ended September 30, 2018 was $870 million, which included $1.3 billion of net discrete tax benefits primarily attributable to excess tax benefits from stock-based compensation. Cash paid for income taxes, net of refunds was $172 million and $200 million in Q3 2017 and Q3 2018, and $865 million and $1.0 billion for the nine months ended September 30, 2017 and 2018. As of December 31, 2017 and September 30, 2018, tax contingencies were approximately $2.3 billion and $3.4 billion. We expect the total amount of tax contingencies will grow in 2018. In addition, changes in state, federal, and foreign tax laws may increase our tax contingencies. The timing of the resolution of income tax examinations is highly uncertain, and the amounts ultimately paid, if any, upon resolution of the issues raised by the taxing authorities may differ from the amounts accrued. It is reasonably possible that within the next 12 months we will receive additional assessments by various tax authorities or possibly reach resolution of income tax examinations in one or more jurisdictions. These assessments or settlements could result in changes to our contingencies related to positions on tax filings on prior years’ tax filings. We are under examination, or may be subject to examination, by the Internal Revenue Service (“IRS”) for the calendar year 2005 and thereafter. These examinations may lead to ordinary course adjustments or proposed adjustments to our taxes or our net operating losses with respect to years under examination as well as subsequent periods. As previously disclosed, we have received Notices of Proposed Adjustment (“NOPAs”) from the IRS for transactions undertaken in the 2005 and 2006 calendar years relating to transfer pricing with our foreign subsidiaries. The IRS is seeking to increase our U.S. taxable income by an amount that would result in additional federal tax of approximately $1.5 billion, subject to interest. On March 23, 2017, the U.S. Tax Court issued its decision regarding the issues raised in the IRS NOPAs. The Tax Court rejected the approach from the IRS NOPAs in determining transfer pricing adjustments in 2005 and 2006 for the transactions undertaken with our foreign subsidiaries and adopted, with adjustments, our suggested approach. In September 2017, the IRS appealed the decision to the U.S. Court of Appeals for the Ninth Circuit. We will continue to defend ourselves vigorously in this matter. If the Tax Court decision were reversed on appeal or if the IRS were to successfully assert transfer pricing adjustments of a similar nature to the NOPAs for transactions in subsequent years, we could be subject to significant additional tax liabilities. In October 2014, the European Commission opened a formal investigation to examine whether decisions by the tax authorities in Luxembourg with regard to the corporate income tax paid by certain of our subsidiaries comply with European Union rules on state aid. On October 4, 2017, the European Commission announced its decision that determinations by the tax authorities in Luxembourg did not comply with European Union rules on state aid. Based on that decision the European Commission announced an estimated recovery amount of approximately €250 million, plus interest, for the period May 2006 through June 2014, and ordered Luxembourg tax authorities to calculate the actual amount of additional taxes subject to recovery. Luxembourg computed an initial recovery amount, consistent with the European Commission’s decision, that we deposited into escrow in March 2018, subject to adjustment pending conclusion of all appeals. In December 2017, Luxembourg appealed the European Commission’s decision. In May 2018, we appealed. We believe the European Commission’s decision to be without merit and will continue to defend ourselves vigorously in this matter. We are also subject to taxation in various states and other foreign jurisdictions including Canada, China, Germany, India, Japan, Luxembourg, and the United Kingdom. We are under, or may be subject to, audit or examination and additional assessments by the relevant authorities in respect of these particular jurisdictions primarily for 2008 and thereafter.

Segment Information

9 Months Ended

Sep. 30, 2018

Segment Reporting [Abstract]

Segment Information

SEGMENT INFORMATION

We have organized our operations into three segments: North America, International, and AWS. We allocate to segment results the operating expenses “Fulfillment,” “Marketing,” “Technology and content,” and “General and administrative” based on usage, which is generally reflected in the segment in which the costs are incurred. The majority of technology infrastructure costs are allocated to the AWS segment based on usage. The majority of the remaining non-infrastructure technology costs are incurred in the U.S. and are allocated to our North America segment. The results of Whole Foods Market are included in our North America and International segments based on physical location. There are no internal revenue transactions between our reportable segments. These segments reflect the way our chief operating decision maker evaluates the Company’s business performance and manages its operations.

North America

The North America segment primarily consists of amounts earned from retail sales of consumer products (including from sellers) and subscriptions through North America-focused websites and physical stores. This segment includes export sales from these websites.

International

The International segment primarily consists of amounts earned from retail sales of consumer products (including from sellers) and subscriptions through internationally-focused websites. This segment includes export sales from these internationally-focused websites (including export sales from these sites to customers in the U.S., Mexico, and Canada), but excludes export sales from our North America-focused websites.

AWS

The AWS segment consists of amounts earned from global sales of compute, storage, database, and other service offerings for start-ups, enterprises, government agencies, and academic institutions.

Information on reportable segments and reconciliation to consolidated net income is as follows (in millions):



	Three Months Ended September 30,						Nine Months Ended September 30,
	2017			2018			2017			2018
North America
Net sales	$	25,446		$	34,348		$	68,808		$	97,242
Operating expenses	25,334			32,316			67,664			92,227
Operating income	$	112		$	2,032		$	1,144		$	5,015

International
Net sales	$	13,714		$	15,549		$	36,259		$	45,037
Operating expenses	14,650			15,934			38,401			46,536
Operating income (loss)	$	(936	)	$	(385	)	$	(2,142	)	$	(1,499	)

AWS
Net sales	$	4,584		$	6,679		$	12,346		$	18,225
Operating expenses	3,413			4,602			9,369			13,106
Operating income	$	1,171		$	2,077		$	2,977		$	5,119

Consolidated
Net sales	$	43,744		$	56,576		$	117,413		$	160,504
Operating expenses	43,397			52,852			115,434			151,869
Operating income	347			3,724			1,979			8,635
Total non-operating income (expense)	(31		)	(334		)	(44		)	(724		)
Provision for income taxes	(58		)	(508		)	(755		)	(870		)
Equity-method investment activity, net of tax	(2		)	1			(4		)	5
Net income	$	256		$	2,883		$	1,176		$	7,046

Net sales by groups of similar products and services, which also have similar economic characteristics, is as follows (in millions):



	Three Months Ended September 30,				Nine Months Ended September 30,
	2017		2018		2017		2018
Net Sales:
Online stores (1)	$	26,392	$	29,061	$	72,971	$	83,165
Physical stores (2)	1,276		4,248		1,276		12,824
Third-party seller services (3)	7,928		10,395		21,357		29,361
Subscription services (4)	2,441		3,698		6,544		10,209
AWS	4,584		6,679		12,346		18,225
Other (5)	1,123		2,495		2,919		6,720
Consolidated	$	43,744	$	56,576	$	117,413	$	160,504

____________________________

(1)

Includes product sales and digital media content where we record revenue gross. We leverage our retail infrastructure to offer a wide selection of consumable and durable goods that includes media products available in both a physical and digital format, such as books, music, videos, games, and software. These product sales include digital products sold on a transactional basis. Digital product subscriptions that provide unlimited viewing or usage rights are included in Subscription services.


(2)	Includes product sales where our customers physically select items in a store.


(3)	Includes commissions and any related fulfillment and shipping fees, and other third-party seller services.


(4)	Includes annual and monthly fees associated with Amazon Prime membership, as well as audiobook, digital video, e-book, digital music, and other non-AWS subscription services.


(5)	Primarily includes sales of advertising services, as well as sales related to our other service offerings.

Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2018

Accounting Policies [Abstract]

Unaudited Interim Financial Information

We have prepared the accompanying consolidated financial statements pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”) for interim financial reporting. These consolidated financial statements are unaudited and, in our opinion, include all adjustments, consisting of normal recurring adjustments and accruals necessary for a fair presentation of our consolidated balance sheets, operating results, and cash flows for the periods presented. Operating results for the periods presented are not necessarily indicative of the results that may be expected for 2018 due to seasonal and other factors. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) have been omitted in accordance with the rules and regulations of the SEC. These consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes in Item 8 of Part II, “Financial Statements and Supplementary Data,” of our 2017 Annual Report on Form 10-K.

Prior Period Reclassifications

Certain prior period amounts have been reclassified to conform to the current period presentation, including the addition of restricted cash to cash and cash equivalents on the consolidated statements of cash flows as a result of the adoption of new accounting guidance.

Principles of Consolidation

The consolidated financial statements include the accounts of Amazon.com, Inc., its wholly-owned subsidiaries, and those entities in which we have a variable interest and of which we are the primary beneficiary, including certain entities in India and China and that support our seller lending financing activities (collectively, the “Company”). Intercompany balances and transactions between consolidated entities are eliminated. The financial results of Whole Foods Market, Inc. (“Whole Foods Market”) have been included in our consolidated financial statements from the date of acquisition on August 28, 2017.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires estimates and assumptions that affect the reported amounts of assets and liabilities, revenues and expenses, and related disclosures of contingent liabilities in the consolidated financial statements and accompanying notes. Estimates are used for, but not limited to, income taxes, commitments and contingencies, valuation of acquired intangibles and goodwill, stock-based compensation forfeiture rates, vendor funding, and inventory valuation. Actual results could differ materially from those estimates.

Earnings per Share

Basic earnings per share is calculated using our weighted-average outstanding common shares. Diluted earnings per share is calculated using our weighted-average outstanding common shares including the dilutive effect of stock awards as determined under the treasury stock method. In periods when we have a net loss, stock awards are excluded from our calculation of earnings per share as their inclusion would have an antidilutive effect.

Revenue from Contracts with Customers, Policy

Revenue

Revenue is measured based on the amount of consideration that we expect to receive, reduced by estimates for return allowances, promotional discounts, and rebates. Revenue also excludes any amounts collected on behalf of third parties, including sales and indirect taxes. In arrangements where we have multiple performance obligations, the transaction price is allocated to each performance obligation using the relative stand-alone selling price. We generally determine stand-alone selling prices based on the prices charged to customers or using expected cost plus a margin.

A description of our principal revenue generating activities is as follows:

Retail sales - We offer consumer products through our online and physical stores. Revenue is recognized when control of the goods is transferred to the customer, which generally occurs upon our delivery to a third-party carrier or, in the case of an Amazon delivery, to the customer.

Third-party seller services - We offer programs that enable sellers to sell their products on our websites and their own branded websites, and fulfill orders through us. We are not the seller of record in these transactions. The commissions and any related fulfillment and shipping fees we earn from these arrangements are recognized when the services are rendered, which generally occurs upon delivery of the related products to a third-party carrier or, in the case of an Amazon delivery, to the customer.

Subscription services - Our subscription sales include fees associated with Amazon Prime memberships and access to content including audiobooks, digital video, e-books, digital music, and other non-AWS subscription services. Prime memberships provide our customers with access to an evolving suite of benefits that represent a single stand-ready obligation. Subscriptions are paid for at the time of or in advance of delivering the services. Revenue from such arrangements is recognized over the subscription period.

AWS - Our AWS arrangements include global sales of compute, storage, database, and other services. Revenue is allocated to services using stand-alone selling prices and is primarily recognized when the customer uses these services, based on the quantity of services rendered, such as compute or storage capacity delivered on-demand. Certain services, including compute and database, are also offered as a fixed quantity over a specified term, for which revenue is recognized ratably. Sales commissions we pay in connection with contracts that exceed one year are capitalized and amortized over the contract term.

Other - Other revenue primarily includes sales of advertising services, which are recognized as ads are delivered based on the number of clicks or impressions.

Return Allowances

Return allowances, which reduce revenue and cost of sales, are estimated using historical experience. Liabilities for return allowances are included in “Accrued expenses and other” and were $468 million and $407 million as of December 31, 2017 and September 30, 2018. Included in “Inventories” on our consolidated balance sheets are assets totaling $406 million and $310 million as of December 31, 2017 and September 30, 2018, for the rights to recover products from customers associated with our liabilities for return allowances.

Cost of Sales

Cost of sales primarily consists of the purchase price of consumer products, digital media content costs where we recognize revenue gross, including video and music, packaging supplies, sortation and delivery centers and related equipment costs, and inbound and outbound shipping costs, including where we are the transportation service provider. Shipping costs to receive products from our suppliers are included in our inventory, and recognized as cost of sales upon sale of products to our customers. Payment processing and related transaction costs, including those associated with seller transactions, are classified in “Fulfillment” on our consolidated statements of operations.

Vendor Agreements

We have agreements with our vendors to receive funds primarily for cooperative marketing efforts, promotions, incentives, and volume rebates. We generally consider these amounts received from vendors to be a reduction of the prices we pay for their goods, including property and equipment, or services, and are recorded as a reduction of the cost of inventory, cost of services, or cost of property and equipment. Volume rebates typically depend on reaching minimum purchase thresholds. We evaluate the likelihood of reaching purchase thresholds using past experience and current year forecasts. When volume rebates can be reasonably estimated, we record a portion of the rebate as we make progress towards the purchase threshold.

Accounts Receivable, Net and Other

Included in “Accounts receivable, net and other” on our consolidated balance sheets are amounts primarily related to customers, vendors, and sellers. As of December 31, 2017 and September 30, 2018, customer receivables, net, were $6.4 billion and $8.4 billion, vendor receivables, net, were $2.6 billion and $2.1 billion, and seller receivables, net, were $692 million and $689 million. Seller receivables are amounts due from sellers related to our seller lending program, which provides funding to sellers primarily to procure inventory.

We estimate losses on receivables based on known troubled accounts and historical experience of losses incurred. Receivables are considered impaired and written-off when it is probable that all contractual payments due will not be collected in accordance with the terms of the agreement. The allowance for doubtful accounts was $348 million and $457 million as of December 31, 2017 and September 30, 2018.

Unearned Revenue

Unearned revenue is recorded when payments are received or due in advance of performing our service obligations and is recognized over the service period. Unearned revenue primarily relates to prepayments of Amazon Prime memberships and AWS services. Our total unearned revenue as of December 31, 2017 was $6.1 billion, of which $4.9 billion was recognized as revenue during the nine months ended September 30, 2018, including adjustments related to the new revenue recognition guidance. Included in “Other long-term liabilities” on our consolidated balance sheets was $1.0 billion and $1.2 billion of unearned revenue as of December 31, 2017 and September 30, 2018.

Additionally, we have performance obligations, primarily related to AWS, associated with commitments in customer contracts for future services that have not yet been recognized in our financial statements. For contracts with original terms that exceed one year, the amount of revenue not yet recognized was $17.8 billion as of September 30, 2018. The weighted average remaining life of our long-term contracts is 3.5 years. However, the timing of revenue recognition is largely driven by customer usage, which can extend beyond the original contractual term.

Accrued Expenses And Other, Policy

Accrued Expenses and Other

Included in “Accrued expenses and other” on our consolidated balance sheets are amounts primarily related to unredeemed gift cards, customer liabilities, leases and asset retirement obligations, current debt, acquired digital media content, and other operating expenses.

As of December 31, 2017 and September 30, 2018, our liabilities for unredeemed gift cards were $3.0 billion and $1.7 billion. We reduce the liability for a gift card when redeemed by a customer. The portion of gift cards that we do not expect to be redeemed is recognized based on customer usage patterns.

Accounting Pronouncements Recently Adopted and Accounting Pronouncements Not Yet Adopted

Accounting Pronouncements Recently Adopted

In May 2014, the FASB issued an Accounting Standards Update (“ASU”) amending revenue recognition guidance and requiring more detailed disclosures to enable users of financial statements to understand the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. We adopted this ASU on January 1, 2018 for all revenue contracts with our customers using the modified retrospective approach and increased retained earnings by approximately $650 million. The adjustment primarily relates to the unredeemed portion of our gift cards, which are now recognized over the expected customer usage period rather than waiting until gift cards expire or when the likelihood of redemption becomes remote. We changed the recognition and classification of Amazon Prime memberships, which are now accounted for as a single performance obligation and recognized ratably over the membership period as service sales. Previously, Prime memberships were considered to be arrangements with multiple deliverables and were allocated among product sales and service sales. Other changes relate primarily to the presentation of revenue. Certain advertising services are now classified as revenue rather than a reduction in cost of sales, and sales of apps, in-app content, and certain digital media content are presented on a net basis.

The impact of applying this ASU for the nine months ended September 30, 2018 primarily resulted in a decrease in product sales and an increase in service sales driven by the reclassification of Prime membership fees of approximately $2.6 billion. Service sales also increased by approximately $2.0 billion for the nine months ended September 30, 2018 due to the reclassification of certain advertising services.

In January 2016, the FASB issued an ASU that updates certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. Under this ASU, certain equity investments are measured at fair value with changes recognized in net income. We adopted this ASU in Q1 2018 with no material impact to our consolidated financial statements.

In October 2016, the FASB issued an ASU amending the accounting for income taxes. The new guidance requires the recognition of the income tax consequences of an intercompany asset transfer, other than transfers of inventory, when the transfer occurs. For intercompany transfers of inventory, the income tax effects will continue to be deferred until the inventory has been sold to a third party. We adopted this ASU in Q1 2018 with an increase of approximately $250 million to retained earnings and deferred tax assets net of valuation allowances.

In November 2016, the FASB issued an ASU amending the presentation of restricted cash within the consolidated statements of cash flows. The new guidance requires that restricted cash be added to cash and cash equivalents on the consolidated statements of cash flows. We adopted this ASU in Q1 2018 on a retrospective basis with the following impacts to our consolidated statements of cash flows (in millions):



Three Months Ended September 30, 2017	Previously Reported			Adjustments			As Revised
Operating activities	$	3,851		$	(74	)	$	3,777
Investing activities	(19,120		)	642			(18,478		)
Financing activities	14,685			(23		)	14,662
Net change in cash, cash equivalents, and restricted cash	$	(584	)	$	545		$	(39	)



Nine Months Ended September 30, 2017	Previously Reported			Adjustments			As Revised
Operating activities	$	6,090		$	(83	)	$	6,007
Investing activities	(25,787		)	684			(25,103		)
Financing activities	12,507			(8		)	12,499
Net change in cash, cash equivalents, and restricted cash	$	(7,190	)	$	593		$	(6,597	)



Twelve Months Ended September 30, 2017	Previously Reported			Adjustments			As Revised
Operating activities	$	17,077		$	(81	)	$	16,996
Investing activities	(29,961		)	792			(29,169		)
Financing activities	11,916			14			11,930
Net change in cash, cash equivalents, and restricted cash	$	(968	)	$	725		$	(243	)

Accounting Pronouncements Not Yet Adopted

In February 2016, the FASB issued an ASU amending the accounting for leases. The new guidance requires the recognition of lease assets and liabilities for operating leases with terms of more than 12 months, in addition to those currently recorded, on our consolidated balance sheets. Presentation of leases within the consolidated statements of operations and consolidated statements of cash flows will be generally consistent with the current lease accounting guidance. The ASU is effective for reporting periods beginning after December 15, 2018, with early adoption permitted. We will adopt this ASU on January 1, 2019 with a cumulative adjustment to retained earnings rather than retrospectively adjusting prior periods. This adoption approach will result in a balance sheet presentation that is not comparable to the prior period in the first year of adoption. To illustrate the magnitude of this change, the amount of our off-balance sheet operating leases at September 30, 2018 is disclosed in “Note 3 — Commitments and Contingencies.” Beginning on January 1, 2019, our operating leases, excluding those with terms less than 12 months, will be discounted and recorded as assets and liabilities on our consolidated balance sheet.

Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2018

Accounting Policies [Abstract]

Calculation of Diluted Shares

The following table shows the calculation of diluted shares (in millions):



	Three Months Ended September 30,		Nine Months Ended September 30,
	2017	2018	2017	2018
Shares used in computation of basic earnings per share	481	488	479	486
Total dilutive effect of outstanding stock awards	13	13	13	14
Shares used in computation of diluted earnings per share	494	501	492	500

Schedule of New Accounting Pronouncements and Changes in Accounting Principles

We adopted this ASU in Q1 2018 on a retrospective basis with the following impacts to our consolidated statements of cash flows (in millions):



Three Months Ended September 30, 2017	Previously Reported			Adjustments			As Revised
Operating activities	$	3,851		$	(74	)	$	3,777
Investing activities	(19,120		)	642			(18,478		)
Financing activities	14,685			(23		)	14,662
Net change in cash, cash equivalents, and restricted cash	$	(584	)	$	545		$	(39	)



Nine Months Ended September 30, 2017	Previously Reported			Adjustments			As Revised
Operating activities	$	6,090		$	(83	)	$	6,007
Investing activities	(25,787		)	684			(25,103		)
Financing activities	12,507			(8		)	12,499
Net change in cash, cash equivalents, and restricted cash	$	(7,190	)	$	593		$	(6,597	)



Twelve Months Ended September 30, 2017	Previously Reported			Adjustments			As Revised
Operating activities	$	17,077		$	(81	)	$	16,996
Investing activities	(29,961		)	792			(29,169		)
Financing activities	11,916			14			11,930
Net change in cash, cash equivalents, and restricted cash	$	(968	)	$	725		$	(243	)

Cash, Cash Equivalents, and Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2018

Investments, Debt and Equity Securities [Abstract]

Fair Value by Major Security Type

The following table summarizes, by major security type, our cash, cash equivalents, restricted cash, and marketable securities that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy (in millions):



	December 31, 2017			September 30, 2018
	Total Estimated Fair Value			Cost or Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Total Estimated Fair Value
Cash	$	9,982		$	8,053	$	—	$	—		$	8,053
Level 1 securities:
Money market funds	11,343			11,128		—		—			11,128
Equity securities	53			28		137		—			165
Level 2 securities:
Foreign government and agency securities	620			481		—		—			481
U.S. government and agency securities	4,823			5,544		1		(26		)	5,519
Corporate debt securities	4,257			4,006		1		(17		)	3,990
Asset-backed securities	905			826		—		(5		)	821
Other fixed income securities	338			189		—		(3		)	186
Equity securities	—			28		3		—			31
	$	32,321		$	30,283	$	142	$	(51	)	$	30,374
Less: Restricted cash, cash equivalents, and marketable securities (1)	(1,335		)								(609		)
Total cash, cash equivalents, and marketable securities	$	30,986									$	29,765

___________________

(1)

We are required to pledge or otherwise restrict a portion of our cash, cash equivalents, and marketable securities as collateral for real estate leases, amounts due to third-party sellers in certain jurisdictions, debt, and standby and trade letters of credit. We classify cash, cash equivalents, and marketable securities with use restrictions of less than twelve months as “Accounts receivable, net and other” and of twelve months or longer as non-current “Other assets” on our consolidated balance sheets. See “Note 3 — Commitments and Contingencies.”

Investments Classified by Contractual Maturity Date

The following table summarizes the remaining contractual maturities of our cash equivalents and marketable fixed income securities as of September 30, 2018 (in millions):



	Amortized Cost		Estimated Fair Value
Due within one year	$	18,390	$	18,380
Due after one year through five years	3,079		3,053
Due after five years through ten years	224		221
Due after ten years	481		471
Total	$	22,174	$	22,125

Actual maturities may differ from the contractual maturities because borrowers may have certain prepayment conditions.

Reconciliation of cash, cash equivalents, and restricted cash

The following table provides a reconciliation of the amount of cash, cash equivalents, and restricted cash reported within the consolidated balance sheets to the total of the same such amounts shown in the consolidated statements of cash flows (in millions):



	December 31, 2017		September 30, 2018
Cash and cash equivalents	$	20,522	$	20,425
Restricted cash included in accounts receivable, net and other	1,329		604
Restricted cash included in other assets	5		3
Total cash, cash equivalents, and restricted cash shown in the consolidated statements of cash flows	$	21,856	$	21,032

Commitments and Contingencies (Tables)

9 Months Ended

Sep. 30, 2018

Commitments and Contingencies Disclosure [Abstract]

Principal Contractual Commitments, Excluding Open Orders for Purchases

The following summarizes our principal contractual commitments, excluding open orders for purchases that support normal operations and are generally cancellable, as of September 30, 2018 (in millions):



	Three Months Ended December 31,		Year Ended December 31,
	2018		2019		2020		2021		2022		Thereafter		Total
Debt principal and interest	$	213	$	2,186	$	2,111	$	1,833	$	2,049	$	31,769	$	40,161
Capital lease obligations, including interest (1)	1,363		6,912		4,753		1,740		583		773		16,124
Finance lease obligations, including interest (2)	145		609		625		636		647		5,654		8,316
Operating leases	748		2,902		2,752		2,468		2,200		13,453		24,523
Unconditional purchase obligations (3)	137		3,760		3,488		3,265		3,054		8,096		21,800
Other commitments (4) (5)	841		1,734		1,157		1,184		649		7,936		13,501
Total commitments	$	3,447	$	18,103	$	14,886	$	11,126	$	9,182	$	67,681	$	124,425

___________________


(1)	Excluding interest, current capital lease obligations of $5.8 billion and $6.9 billion are recorded within “Accrued expenses and other” as of December 31, 2017 and September 30, 2018, and $8.4 billion and $8.7 billion are recorded within “Other long-term liabilities” as of December 31, 2017 and September 30, 2018.


(2)	Excluding interest, current finance lease obligations of $282 million and $391 million are recorded within “Accrued expenses and other” as of December 31, 2017 and September 30, 2018, and $4.7 billion and $6.5 billion are recorded within “Other long-term liabilities” as of December 31, 2017 and September 30, 2018.

(3)

Includes unconditional purchase obligations related to certain products offered in our Whole Foods Market stores and long-term agreements to acquire and license digital media content that are not reflected on the consolidated balance sheets. For those digital media content agreements with variable terms, we do not estimate the total obligation beyond any minimum quantities and/or pricing as of the reporting date. Purchase obligations associated with renewal provisions solely at the option of the content provider are included to the extent such commitments are fixed or a minimum amount is specified.


(4)	Includes the estimated timing and amounts of payments for rent and tenant improvements associated with build-to-suit lease arrangements and equipment lease arrangements that have not been placed in service and digital media content liabilities associated with long-term digital media content assets with initial terms greater than one year.


(5)	Excludes approximately $3.4 billion of accrued tax contingencies for which we cannot make a reasonably reliable estimate of the amount and period of payment, if any.

Acquisitions, Goodwill, and Acquired Intangible Assets Acquisitions, Goodwill, and Acquired Intangible Assets (Tables)

9 Months Ended

Sep. 30, 2018

Business Acquisition [Line Items]

Schedule of Recognized Identified Assets Acquired and Liabilities Assumed

The aggregate purchase price of Ring, PillPack, and the other 2018 acquisitions was allocated as follows (in millions):



Purchase Price
Cash paid, net of cash acquired	$	1,609
Indemnification holdback	29
	$	1,638

Allocation
Goodwill	$	1,222
Intangible assets (1):
Marketing-related	186
Contract-based	13
Technology-based	279
Customer-related	193
	671
Property and equipment	11
Deferred tax assets	174
Other assets acquired	282
Long-term debt	(176		)
Deferred tax liabilities	(159		)
Other liabilities assumed	(387		)
	$	1,638

___________________


(1)	Acquired intangible assets have estimated useful lives of between two and seven years, with a weighted-average amortization period of six years.

Schedule of Goodwill

The following summarizes our goodwill activity in the first nine months of 2018 by segment (in millions):



	North America			International			AWS			Consolidated
Goodwill - December 31, 2017	$	11,165		$	1,108		$	1,077		$	13,350
New acquisitions (1)	1,030			177			15			1,222
Other adjustments (2)	(2		)	(10		)	(7		)	(19		)
Goodwill - September 30, 2018	$	12,193		$	1,275		$	1,085		$	14,553

___________________


(1)	Primarily includes the acquisitions of Ring and PillPack in the North America and International segments.


(2)	Primarily includes changes in foreign exchange rates.

Long-Term Debt (Tables)

9 Months Ended

Sep. 30, 2018

Debt Disclosure [Abstract]

Long-Term Debt Obligations

The face value of our total long-term debt obligations is as follows (in millions):



	December 31, 2017			September 30, 2018
2.600% Notes due on December 5, 2019 (2)	1,000			1,000
1.900% Notes due on August 21, 2020 (3)	1,000			1,000
3.300% Notes due on December 5, 2021 (2)	1,000			1,000
2.500% Notes due on November 29, 2022 (1)	1,250			1,250
2.400% Notes due on February 22, 2023 (3)	1,000			1,000
2.800% Notes due on August 22, 2024 (3)	2,000			2,000
3.800% Notes due on December 5, 2024 (2)	1,250			1,250
5.200% Notes due on December 3, 2025 (4)	1,000			1,000
3.150% Notes due on August 22, 2027 (3)	3,500			3,500
4.800% Notes due on December 5, 2034 (2)	1,250			1,250
3.875% Notes due on August 22, 2037 (3)	2,750			2,750
4.950% Notes due on December 5, 2044 (2)	1,500			1,500
4.050% Notes due on August 22, 2047 (3)	3,500			3,500
4.250% Notes due on August 22, 2057 (3)	2,250			2,250
Credit Facility	592			535
Other long-term debt	100			44
Total debt	24,942			24,829
Less current portion of long-term debt	(100		)	(44		)
Face value of long-term debt	$	24,842		$	24,785

_____________________________


(1)	Issued in November 2012, effective interest rate of the 2022 Notes was 2.66%.


(2)	Issued in December 2014, effective interest rates of the 2019, 2021, 2024, 2034, and 2044 Notes were 2.73%, 3.43%, 3.90%, 4.92%, and 5.11%.


(3)	Issued in August 2017, effective interest rates of the 2020, 2023, 2024, 2027, 2037, 2047, and 2057 Notes were 2.16%, 2.56%, 2.95%, 3.25%, 3.94%, 4.13%, and 4.33%.


(4)	Consists of $872 million of 2025 Notes issued in December 2017 in exchange for notes assumed in connection with the acquisition of Whole Foods Market and $128 million of 2025 Notes issued by Whole Foods Market that did not participate in our December 2017 exchange offer. The effective interest rate of the 2025 Notes was 3.02%.

- 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
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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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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Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
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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
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-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 505
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+ Details

Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation Expense

Stock-based compensation expense is as follows (in millions):



	Three Months Ended September 30,				Nine Months Ended September 30,
	2017		2018		2017		2018
Cost of sales	$	13	$	19	$	33	$	52
Fulfillment	230		269		655		834
Marketing	135		201		363		552
Technology and content	595		719		1,668		2,138
General and administrative	112		142		317		426
Total stock-based compensation expense	$	1,085	$	1,350	$	3,036	$	4,002

Nonvested Restricted Stock Units Activity

The following table summarizes our restricted stock unit activity for the nine months ended September 30, 2018 (in millions):



	Number of Units		Weighted-Average Grant-Date Fair Value
Outstanding as of December 31, 2017	20.1		$	725
Units granted	4.4		1,512
Units vested	(4.8	)	551
Units forfeited	(1.7	)	831
Outstanding as of September 30, 2018	18.0		$	954

Scheduled Vesting Restricted Stock Unit Activity

Scheduled vesting for outstanding restricted stock units as of September 30, 2018, is as follows (in millions):



	Three Months Ended December 31,	Year Ended December 31,
	2018	2019	2020	2021	2022	Thereafter	Total
Scheduled vesting—restricted stock units	2.3	7.0	5.6	2.3	0.6	0.2	18.0

Segment Information (Tables)

9 Months Ended

Sep. 30, 2018

Segment Reporting [Abstract]

Information on Reportable Segments and Reconciliation to Consolidated Net Income

Information on reportable segments and reconciliation to consolidated net income is as follows (in millions):



	Three Months Ended September 30,						Nine Months Ended September 30,
	2017			2018			2017			2018
North America
Net sales	$	25,446		$	34,348		$	68,808		$	97,242
Operating expenses	25,334			32,316			67,664			92,227
Operating income	$	112		$	2,032		$	1,144		$	5,015

International
Net sales	$	13,714		$	15,549		$	36,259		$	45,037
Operating expenses	14,650			15,934			38,401			46,536
Operating income (loss)	$	(936	)	$	(385	)	$	(2,142	)	$	(1,499	)

AWS
Net sales	$	4,584		$	6,679		$	12,346		$	18,225
Operating expenses	3,413			4,602			9,369			13,106
Operating income	$	1,171		$	2,077		$	2,977		$	5,119

Consolidated
Net sales	$	43,744		$	56,576		$	117,413		$	160,504
Operating expenses	43,397			52,852			115,434			151,869
Operating income	347			3,724			1,979			8,635
Total non-operating income (expense)	(31		)	(334		)	(44		)	(724		)
Provision for income taxes	(58		)	(508		)	(755		)	(870		)
Equity-method investment activity, net of tax	(2		)	1			(4		)	5
Net income	$	256		$	2,883		$	1,176		$	7,046

Disaggregation of Revenue

Net sales by groups of similar products and services, which also have similar economic characteristics, is as follows (in millions):



	Three Months Ended September 30,				Nine Months Ended September 30,
	2017		2018		2017		2018
Net Sales:
Online stores (1)	$	26,392	$	29,061	$	72,971	$	83,165
Physical stores (2)	1,276		4,248		1,276		12,824
Third-party seller services (3)	7,928		10,395		21,357		29,361
Subscription services (4)	2,441		3,698		6,544		10,209
AWS	4,584		6,679		12,346		18,225
Other (5)	1,123		2,495		2,919		6,720
Consolidated	$	43,744	$	56,576	$	117,413	$	160,504

____________________________

(1)

Includes product sales and digital media content where we record revenue gross. We leverage our retail infrastructure to offer a wide selection of consumable and durable goods that includes media products available in both a physical and digital format, such as books, music, videos, games, and software. These product sales include digital products sold on a transactional basis. Digital product subscriptions that provide unlimited viewing or usage rights are included in Subscription services.


(2)	Includes product sales where our customers physically select items in a store.


(3)	Includes commissions and any related fulfillment and shipping fees, and other third-party seller services.


(4)	Includes annual and monthly fees associated with Amazon Prime membership, as well as audiobook, digital video, e-book, digital music, and other non-AWS subscription services.


(5)	Primarily includes sales of advertising services, as well as sales related to our other service offerings.

Accounting Policies - Calculation of Diluted Shares (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Accounting Policies [Abstract]
Shares used in computation of basic earnings per share	488	481	486	479
Total dilutive effect of outstanding stock awards	13	13	14	13
Shares used in computation of diluted earnings per share	501	494	500	492

Accounting Policies - Return Allowances (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Contract with Customer, Refund Liability	$ 407	$ 468
Contract with Customer, Right to Recover Product	$ 310	$ 406

Accounting Policies - Accounts Receivable, Net and Other (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net and other	$ 14,258	$ 13,164
Allowance for Doubtful Accounts Receivable, Current	457	348
Customer Receivables, net
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net and other	8,400	6,400
Vendor Receivables, net
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net and other	2,100	2,600
Seller Receivables, net
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net and other	$ 689	$ 692

Accounting Policies - Unearned Revenue (Details) - USD ($) $ in Billions	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Unearned revenue		$ 6.1
Unearned revenue, revenue recognized from beginning balance	$ 4.9
Unearned Revenue, Noncurrent	1.2	$ 1.0
Remaining performance obligation, contracts exceeding one year	$ 17.8
Remaining performance obligation, expected timing of satisfaction, weighted average remaining life	3 years 6 months

Accounting Policies - Accrued Expenses and Other (Details) - USD ($) $ in Billions	Sep. 30, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Unredeemed gift certificates	$ 1.7	$ 3.0

Accounting Policies - Revenue, Initial Application Period Cumulative Effect Transition (Details) - Difference between Revenue Guidance in Effect before and after Topic 606 [Member] $ in Billions	9 Months Ended
	Sep. 30, 2018 USD ($)
Service, Subscription [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net sales	$ 2.6
Product, Subscription [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net sales	(2.6)
Service, Other [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net sales	$ 2.0

Accounting Policies - Accounting Pronouncements Recently Adopted (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Mar. 31, 2018	Jan. 01, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net Cash Provided by (Used in) Operating Activities	$ 8,588	$ 3,777	$ 14,246	$ 6,007	$ 26,604	$ 16,996
Net Cash Provided by (Used in) Investing Activities	(5,572)	(18,478)	(8,797)	(25,103)	(10,778)	(29,169)
Net Cash Provided by (Used in) Financing Activities	$ (2,369)	14,662	$ (5,925)	12,499	$ (8,496)	11,930
Net change in cash, cash equivalents, and restricted cash		(39)		(6,597)		(243)
Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets								$ 650
Accounting Standards Update 2016-16 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets							$ 250
Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net Cash Provided by (Used in) Operating Activities		3,851		6,090		17,077
Net Cash Provided by (Used in) Investing Activities		(19,120)		(25,787)		(29,961)
Net Cash Provided by (Used in) Financing Activities		14,685		12,507		11,916
Net change in cash, cash equivalents, and restricted cash		(584)		(7,190)		(968)
Restatement Adjustment [Member] \| Accounting Standards Update 2016-18 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net Cash Provided by (Used in) Operating Activities		(74)		(83)		(81)
Net Cash Provided by (Used in) Investing Activities		642		684		792
Net Cash Provided by (Used in) Financing Activities		(23)		(8)		14
Net change in cash, cash equivalents, and restricted cash		$ 545		$ 593		$ 725

Cash, Cash Equivalents, and Marketable Securities - Fair Values on Recurring Basis (Details) - Recurring - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Schedule of Investments [Line Items]
Cash	$ 8,053	$ 9,982
Total Estimated Fair Value
Cash, cash equivalents and short-term investments	30,374	32,321
Less: Restricted cash, cash equivalents, and marketable securities	(609)	(1,335)
Total cash, cash equivalents, and marketable securities	29,765	30,986
Cost or Amortized Cost
Cash, cash equivalents and short-term investments	30,283
Gross Unrealized Gains
Equity and Available For Sale Debt Securities Unrealized Gains	142
Gross Unrealized Losses
Debt Securities, Available for Sale, Unrealized Loss	(51)
Level 1 securities
Total Estimated Fair Value
Equity Securities, FV-NI	165	53
Cost or Amortized Cost
Equity Securities, FV-NI, Cost	28
Gross Unrealized Gains
Equity Securities, FV-NI, Unrealized Gain	137
Gross Unrealized Losses
Equity Securities, FV-NI, Unrealized Loss	0
Level 1 securities \| Money market funds
Schedule of Investments [Line Items]
Money market funds	11,128	11,343
Level 2 securities
Total Estimated Fair Value
Equity Securities, FV-NI	31	0
Cost or Amortized Cost
Equity Securities, FV-NI, Cost	28
Gross Unrealized Gains
Equity Securities, FV-NI, Unrealized Gain	3
Gross Unrealized Losses
Equity Securities, FV-NI, Unrealized Loss	0
Level 2 securities \| Foreign government and agency securities
Total Estimated Fair Value
Debt Securities, Available for Sale, Fair Value	481	620
Cost or Amortized Cost
Debt Securities, Available for Sale, Cost	481
Gross Unrealized Gains
Debt Securities, Available for Sale, Unrealized Gain	0
Gross Unrealized Losses
Debt Securities, Available for Sale, Unrealized Loss	0
Level 2 securities \| U.S. government and agency securities
Total Estimated Fair Value
Debt Securities, Available for Sale, Fair Value	5,519	4,823
Cost or Amortized Cost
Debt Securities, Available for Sale, Cost	5,544
Gross Unrealized Gains
Debt Securities, Available for Sale, Unrealized Gain	1
Gross Unrealized Losses
Debt Securities, Available for Sale, Unrealized Loss	(26)
Level 2 securities \| Corporate debt securities
Total Estimated Fair Value
Debt Securities, Available for Sale, Fair Value	3,990	4,257
Cost or Amortized Cost
Debt Securities, Available for Sale, Cost	4,006
Gross Unrealized Gains
Debt Securities, Available for Sale, Unrealized Gain	1
Gross Unrealized Losses
Debt Securities, Available for Sale, Unrealized Loss	(17)
Level 2 securities \| Asset-backed securities
Total Estimated Fair Value
Debt Securities, Available for Sale, Fair Value	821	905
Cost or Amortized Cost
Debt Securities, Available for Sale, Cost	826
Gross Unrealized Gains
Debt Securities, Available for Sale, Unrealized Gain	0
Gross Unrealized Losses
Debt Securities, Available for Sale, Unrealized Loss	(5)
Level 2 securities \| Other fixed income securities
Total Estimated Fair Value
Debt Securities, Available for Sale, Fair Value	186	$ 338
Cost or Amortized Cost
Debt Securities, Available for Sale, Cost	189
Gross Unrealized Gains
Debt Securities, Available for Sale, Unrealized Gain	0
Gross Unrealized Losses
Debt Securities, Available for Sale, Unrealized Loss	$ (3)

Cash, Cash Equivalents, and Marketable Securities - Contractual Maturities (Details) $ in Millions	Sep. 30, 2018 USD ($)
Amortized Cost
Due within one year	$ 18,390
Due after one year through five years	3,079
Due after five years through ten years	224
Due after ten years	481
Cash Equivalents and Marketable Fixed Income Securities, Cost	22,174
Estimated Fair Value
Due within one year	18,380
Due after one year through five years	3,053
Due after five years through ten years	221
Due after ten years	471
Cash Equivalents and Marketable Fixed Income Securities, Fair Value	$ 22,125

Cash, Cash Equivalents, and Marketable Securities - Additional Information (Details) - Warrant - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Investments, Warrant Assets
Gain (loss) on warrant assets	$ (62)	$ 76	$ 25	$ 145
Level 2 assets
Investments, Warrant Assets
Fair value of warrant assets	$ 573		$ 573		$ 441

Cash, Cash Equivalents, and Marketable Securities - Reconciliation to Cash Flow (Details) - USD ($) $ in Millions	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Reconciliation to Cash Flow [Abstract]
Cash and cash equivalents	$ 20,425		$ 20,522
Restricted cash included in accounts receivable, net and other	604		1,329
Restricted cash included in other assets	3		5
Total cash, cash equivalents, and restricted cash shown in the consolidated statements of cash flows	$ 21,032	$ 20,536	$ 21,856	$ 13,960	$ 13,851	$ 19,934	$ 14,124

Commitments and Contingencies - Commitments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Rental expense under operating lease agreements	$ 859	$ 553	$ 2,500	$ 1,400

Commitments and Contingencies - Principal Contractual Commitments Excluding Open Orders (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Debt principal and interest
Three Months Ended December 31, 2018	$ 213
Year Ended December 31, 2019	2,186
Year Ended December 31, 2020	2,111
Year Ended December 31, 2021	1,833
Year Ended December 31, 2022	2,049
Thereafter	31,769
Total	40,161
Capital lease obligations, including interest
Three Months Ended December 31, 2018	1,363
Year Ended December 31, 2019	6,912
Year Ended December 31, 2020	4,753
Year Ended December 31, 2021	1,740
Year Ended December 31, 2022	583
Thereafter	773
Total	16,124
Current capital lease obligations	6,900	$ 5,800
Noncurrent capital lease obligations	8,700	8,400
Finance lease obligations, including interest
Three Months Ended December 31, 2018	145
Year Ended December 31, 2019	609
Year Ended December 31, 2020	625
Year Ended December 31, 2021	636
Year Ended December 31, 2022	647
Thereafter	5,654
Total	8,316
Current finance lease obligations	391	282
Noncurrent finance lease obligations	6,500	4,700
Operating leases
Three Months Ended December 31, 2018	748
Year Ended December 31, 2019	2,902
Year Ended December 31, 2020	2,752
Year Ended December 31, 2021	2,468
Year Ended December 31, 2022	2,200
Thereafter	13,453
Total	24,523
Unconditional purchase obligations
Three Months Ended December 31, 2018	137
Year Ended December 31, 2019	3,760
Year Ended December 31, 2020	3,488
Year Ended December 31, 2021	3,265
Year Ended December 31, 2022	3,054
Thereafter	8,096
Total	21,800
Other commitments
Three Months Ended December 31, 2018	841
Year Ended December 31, 2019	1,734
Year Ended December 31, 2020	1,157
Year Ended December 31, 2021	1,184
Year Ended December 31, 2022	649
Thereafter	7,936
Total	13,501
Accrued tax contingencies	3,400	$ 2,300
Total commitments
Three Months Ended December 31, 2018	3,447
Year Ended December 31, 2019	18,103
Year Ended December 31, 2020	14,886
Year Ended December 31, 2021	11,126
Year Ended December 31, 2022	9,182
Thereafter	67,681
Total	$ 124,425

Commitments and Contingencies - Pledged Assets (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Pledged assets	$ 688	$ 1,400

Acquisitions, Goodwill, and Acquired Intangible Assets - Additional Information (Details) - USD ($) $ in Millions			3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 11, 2018	Apr. 12, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired			$ 976	$ 13,213	$ 1,855	$ 13,891	$ 1,936	$ 13,893
Ring, Inc [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired		$ 839
PillPack, Inc. [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired	$ 753
Other 2018 Acquisitions [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred					$ 46

Acquisitions, Goodwill, and Acquired Intangible Assets - Allocation of Aggregate Purchase Price of Acquisitions (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired	$ 976	$ 13,213	$ 1,855	$ 13,891	$ 1,936	$ 13,893
Goodwill	14,553		14,553		14,553		$ 13,350
Two Thousand Eighteen Acquisitions [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired			1,609
Business Combination, Consideration Transferred, Liabilities Incurred			29
Aggregate purchase price			1,638
Goodwill	1,222		1,222		1,222
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	671		671		671
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	11		11		11
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	174		174		174
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Other Assets	282		282		282
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt	(176)		(176)		(176)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	159		159		159
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Liabilities, Other	387		387		387
Allocated purchase price	1,638		$ 1,638		1,638
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			6 years
Marketing-Related Intangible Assets [Member] \| Two Thousand Eighteen Acquisitions [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	186		$ 186		186
Contract-Based Intangible Assets [Member] \| Two Thousand Eighteen Acquisitions [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	13		13		13
Technology-Based Intangible Assets [Member] \| Two Thousand Eighteen Acquisitions [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	279		279		279
Customer-Related Intangible Assets [Member] \| Two Thousand Eighteen Acquisitions [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 193		$ 193		$ 193
Minimum [Member] \| Two Thousand Eighteen Acquisitions [Member]
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life			2 years
Maximum [Member] \| Two Thousand Eighteen Acquisitions [Member]
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life			7 years

Acquisitions, Goodwill, and Acquired Intangible Assets - Summary of Goodwill Activity by Segment (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill	$ 14,553	$ 13,350
Goodwill, Acquired During Period	1,222
Goodwill, Translation and Purchase Accounting Adjustments	(19)
North America
Goodwill [Line Items]
Goodwill	12,193	11,165
Goodwill, Acquired During Period	1,030
Goodwill, Translation and Purchase Accounting Adjustments	(2)
International
Goodwill [Line Items]
Goodwill	1,275	1,108
Goodwill, Acquired During Period	177
Goodwill, Translation and Purchase Accounting Adjustments	(10)
AWS
Goodwill [Line Items]
Goodwill	1,085	$ 1,077
Goodwill, Acquired During Period	15
Goodwill, Translation and Purchase Accounting Adjustments	$ (7)

Debt - Additional Information (Details)	1 Months Ended
Debt - Additional Information (Details)	Apr. 30, 2018 USD ($) extension	Oct. 31, 2016 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Borrowings outstanding			$ 24,829,000,000	$ 24,942,000,000
Face value of long-term debt			24,785,000,000	24,842,000,000
Commercial Paper
Debt Instrument [Line Items]
Credit term	397 days
Commercial Paper			0
Commercial Paper, Maximum Borrowing Capacity	$ 7,000,000,000
Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount (Premium), Net			101,000,000	99,000,000
Borrowings outstanding			24,300,000,000
Estimated fair value of notes			24,200,000,000	25,700,000,000
Senior Notes \| 5.200% Notes due on December 3, 2025 (4)
Debt Instrument [Line Items]
Borrowings outstanding			1,000,000,000	1,000,000,000
Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Borrowings outstanding			535,000,000	592,000,000
Credit Facility \| Revolving Credit Facility \| October 2016 Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit maximum borrowing capacity		$ 500,000,000	600,000,000
Credit term		3 years
Commitment fee percentage		0.50%
Borrowings outstanding			$ 535,000,000	$ 592,000,000
Weighted average interest rate			3.00%	2.70%
Collateral amount			$ 620,000,000	$ 686,000,000
Credit Facility \| Revolving Credit Facility \| October 2016 Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)		1.65%
Credit Facility \| Revolving Credit Facility \| April 2018 Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit maximum borrowing capacity	$ 7,000,000,000
Credit term	3 years
Line Of Credit Facility, Number Of Extensions \| extension	3
Line Of Credit Facility, Additional Term	1 year
Commitment fee percentage	0.04%
Borrowings outstanding			0	0
Credit Facility \| Revolving Credit Facility \| April 2018 Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	0.50%
Amazon.com, Inc. \| 5.200% Notes due on December 3, 2025 (4)
Debt Instrument [Line Items]
Borrowings outstanding				872,000,000
Whole Foods Market, Inc. \| 5.200% Notes due on December 3, 2025 (4)
Debt Instrument [Line Items]
Borrowings outstanding				128,000,000
Line of Credit and Other Long-term Debt
Debt Instrument [Line Items]
Borrowings outstanding			579,000,000	692,000,000
Other Long-term Debt
Debt Instrument [Line Items]
Borrowings outstanding			$ 44,000,000	$ 100,000,000
Weighted average interest rate			7.30%	5.80%

Debt - Long-Term Debt Obligations (Details) - USD ($)	Sep. 30, 2018	Apr. 30, 2018	Dec. 31, 2017	Oct. 31, 2016
Debt Instrument [Line Items]
Total debt	$ 24,829,000,000		$ 24,942,000,000
Less current portion of long-term debt	(44,000,000)		(100,000,000)
Face value of long-term debt	24,785,000,000		24,842,000,000
Senior Notes
Debt Instrument [Line Items]
Total debt	$ 24,300,000,000
Senior Notes \| 2.600% Notes due on December 5, 2019 (2)
Debt Instrument [Line Items]
Stated interest rate	2.60%
Total debt	$ 1,000,000,000		1,000,000,000
Effective interest rates	2.73%
Senior Notes \| 1.900% Notes due on August 21, 2020 (3)
Debt Instrument [Line Items]
Stated interest rate	1.90%
Total debt	$ 1,000,000,000		1,000,000,000
Effective interest rates	2.16%
Senior Notes \| 3.300% Notes due on December 5, 2021 (2)
Debt Instrument [Line Items]
Stated interest rate	3.30%
Total debt	$ 1,000,000,000		1,000,000,000
Effective interest rates	3.43%
Senior Notes \| 2.500% Notes due on November 29, 2022 (1)
Debt Instrument [Line Items]
Stated interest rate	2.50%
Total debt	$ 1,250,000,000		1,250,000,000
Effective interest rates	2.66%
Senior Notes \| 2.400% Notes due on February 22, 2023 (3)
Debt Instrument [Line Items]
Stated interest rate	2.40%
Total debt	$ 1,000,000,000		1,000,000,000
Effective interest rates	2.56%
Senior Notes \| 2.800% Notes due on August 22, 2024 (3)
Debt Instrument [Line Items]
Stated interest rate	2.80%
Total debt	$ 2,000,000,000		2,000,000,000
Effective interest rates	2.95%
Senior Notes \| 3.800% Notes due on December 5, 2024 (2)
Debt Instrument [Line Items]
Stated interest rate	3.80%
Total debt	$ 1,250,000,000		1,250,000,000
Effective interest rates	3.90%
Senior Notes \| 5.200% Notes due on December 3, 2025 (4)
Debt Instrument [Line Items]
Stated interest rate	5.20%
Total debt	$ 1,000,000,000		1,000,000,000
Effective interest rates	3.02%
Senior Notes \| 3.150% Notes due on August 22, 2027 (3)
Debt Instrument [Line Items]
Stated interest rate	3.15%
Total debt	$ 3,500,000,000		3,500,000,000
Effective interest rates	3.25%
Senior Notes \| 4.800% Notes due on December 5, 2034 (2)
Debt Instrument [Line Items]
Stated interest rate	4.80%
Total debt	$ 1,250,000,000		1,250,000,000
Effective interest rates	4.92%
Senior Notes \| 3.875% Notes due on August 22, 2037 (3)
Debt Instrument [Line Items]
Stated interest rate	3.875%
Total debt	$ 2,750,000,000		2,750,000,000
Effective interest rates	3.94%
Senior Notes \| 4.950% Notes due on December 5, 2044 (2)
Debt Instrument [Line Items]
Stated interest rate	4.95%
Total debt	$ 1,500,000,000		1,500,000,000
Effective interest rates	5.11%
Senior Notes \| 4.050% Notes due on August 22, 2047 (3)
Debt Instrument [Line Items]
Stated interest rate	4.05%
Total debt	$ 3,500,000,000		3,500,000,000
Effective interest rates	4.13%
Senior Notes \| 4.250% Notes due on August 22, 2057 (3)
Debt Instrument [Line Items]
Stated interest rate	4.25%
Total debt	$ 2,250,000,000		2,250,000,000
Effective interest rates	4.33%
Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Total debt	$ 535,000,000		592,000,000
Credit Facility \| October 2016 Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit maximum borrowing capacity	600,000,000			$ 500,000,000
Credit Facility \| April 2018 Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit maximum borrowing capacity		$ 7,000,000,000
Other long-term debt
Debt Instrument [Line Items]
Total debt	$ 44,000,000		$ 100,000,000

Stockholders' Equity - Additional Information (Details) - USD ($) shares in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Feb. 29, 2016
Class of Stock [Line Items]
Common shares outstanding plus underlying outstanding stock awards	507		504
Net unrecognized compensation cost related to unvested stock-based compensation arrangements	$ 7,300,000,000
Compensation cost expected to be expensed in next twelve months, percentage	50.00%
Net unrecognized compensation cost related to unvested stock-based compensation arrangements, weighted average recognition period (in years)	1 year 1 month
Estimated forfeiture rate	27.00%		28.00%
February 2016 Program
Class of Stock [Line Items]
Stock repurchase, authorized amount				$ 5,000,000,000
Stock Repurchased During Period, Value	$ 0	$ 0

Stockholders' Equity - Stock-based Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 1,350	$ 1,085	$ 4,002	$ 3,036
Cost of sales
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	19	13	52	33
Fulfillment
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	269	230	834	655
Marketing
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	201	135	552	363
Technology and content
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	719	595	2,138	1,668
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 142	$ 112	$ 426	$ 317

Stockholders' Equity - Restricted Stock Unit Activity (Details) - Restricted Stock Units shares in Millions	9 Months Ended
	Sep. 30, 2018 $ / shares shares
Number of Units
Beginning balance (in shares) \| shares	20.1
Units granted (in shares) \| shares	4.4
Units vested (in shares) \| shares	(4.8)
Units forfeited (in shares) \| shares	(1.7)
Ending balance (in shares) \| shares	18.0
Weighted-Average Grant-Date Fair Value
Outstanding as of December 31, 2017 \| $ / shares	$ 725
Units granted \| $ / shares	1,512
Units vested \| $ / shares	551
Units forfeited \| $ / shares	831
Outstanding as of September 30, 2018 \| $ / shares	$ 954

Stockholders' Equity - Scheduled Vesting for Outstanding Restricted Stock Units (Details) - Restricted Stock Units - shares shares in Millions	Sep. 30, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Three Months Ended December 31, 2018	2.3
Year Ended December 31, 2019	7.0
Year Ended December 31, 2020	5.6
Year Ended December 31, 2021	2.3
Year Ended December 31, 2022	0.6
Thereafter	0.2
Total	18.0	20.1

- Income Taxes (Details) € in Millions, $ in Millions		3 Months Ended			9 Months Ended		12 Months Ended
- Income Taxes (Details) € in Millions, $ in Millions	Oct. 04, 2017 EUR (€)	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)
Income Tax Disclosure [Abstract]
Provision for income taxes		$ 508		$ 58	$ 870	$ 755
Discrete tax benefits					1,300	422
Cash taxes paid, net of refunds		200		$ 172	1,013	$ 865	$ 1,106	$ 960
Tax contingencies		$ 3,400	$ 2,300		3,400		$ 3,400
Income Tax Examination [Line Items]
Provisional tax benefit for impact of the Act			$ 789
Internal Revenue Service (IRS) \| Domestic Tax Authority [Member]
Income Tax Examination [Line Items]
Tax examination, estimate of additional tax expense					$ 1,500
Luxembourg Tax Administration [Member] \| Foreign Tax Authority [Member]
Income Tax Examination [Line Items]
Tax examination, estimate of additional tax expense \| €	€ 250

Segment Information - Reportable Segments and Reconciliation to Consolidated Net Income (Details) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) segment	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)
Segment Reporting [Abstract]
Number of operating segments \| segment			3
Segment Reporting Disclosure [Line Items]
Net sales	$ 56,576	$ 43,744	$ 160,504	$ 117,413
Operating expenses	52,852	43,397	151,869	115,434
Operating income (loss)	3,724	347	8,635	1,979
Total non-operating income (expense)	(334)	(31)	(724)	(44)
Provision for income taxes	(508)	(58)	(870)	(755)
Equity-method investment activity, net of tax	1	(2)	5	(4)
Net income	2,883	256	7,046	1,176	$ 8,902	$ 1,926
North America
Segment Reporting Disclosure [Line Items]
Net sales	34,348	25,446	97,242	68,808
Operating expenses	32,316	25,334	92,227	67,664
Operating income (loss)	2,032	112	5,015	1,144
International
Segment Reporting Disclosure [Line Items]
Net sales	15,549	13,714	45,037	36,259
Operating expenses	15,934	14,650	46,536	38,401
Operating income (loss)	(385)	(936)	(1,499)	(2,142)
AWS
Segment Reporting Disclosure [Line Items]
Net sales	6,679	4,584	18,225	12,346
Operating expenses	4,602	3,413	13,106	9,369
Operating income (loss)	$ 2,077	$ 1,171	$ 5,119	$ 2,977

Segment Information - 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
Disaggregation of Revenue [Line Items]
Total net sales	$ 56,576	$ 43,744	$ 160,504	$ 117,413
Online stores (1)
Disaggregation of Revenue [Line Items]
Total net sales	29,061	26,392	83,165	72,971
Physical stores (2)
Disaggregation of Revenue [Line Items]
Total net sales	4,248	1,276	12,824	1,276
Third-party seller services (3)
Disaggregation of Revenue [Line Items]
Total net sales	10,395	7,928	29,361	21,357
Subscription services (4)
Disaggregation of Revenue [Line Items]
Total net sales	3,698	2,441	10,209	6,544
AWS
Disaggregation of Revenue [Line Items]
Total net sales	6,679	4,584	18,225	12,346
Other (5)
Disaggregation of Revenue [Line Items]
Total net sales	$ 2,495	$ 1,123	$ 6,720	$ 2,919