DESCRIPTION OF BUSINESS AND ACCOUNTING POLICIES

Description of Business

We seek to be Earth’s most customer-centric company. In each of our segments, we serve our primary customer sets, consisting of consumers, sellers, developers, enterprises, and content creators. We serve consumers through our online and physical stores and focus on selection, price, and convenience. We offer programs that enable sellers to sell their products in our stores and fulfill orders through us, and programs that allow authors, musicians, filmmakers, skill and app developers, and others to publish and sell content. We serve developers and enterprises of all sizes through our AWS segment, which offers a broad set of global compute, storage, database, and other service offerings. We also manufacture and sell electronic devices. In addition, we provide services, such as advertising.

We have organized our operations into three segments: North America, International, and AWS. See “Note 10 — Segment Information.”

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 our 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):



	Year Ended December 31,
	2016	2017	2018
Shares used in computation of basic earnings per share	474	480	487
Total dilutive effect of outstanding stock awards	10	13	13
Shares used in computation of diluted earnings per share	484	493	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 in our stores, 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 $567 million, $468 million, and $623 million as of December 31, 2016, 2017, and 2018. Additions to the allowance were $1.5 billion, $1.8 billion, and $2.3 billion and deductions from the allowance were $1.5 billion, $1.9 billion, and $2.3 billion in 2016, 2017, and 2018. Included in “Inventories” on our consolidated balance sheets are assets totaling $411 million, $406 million, and $519 million as of December 31, 2016, 2017, and 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 record 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.

Fulfillment

Fulfillment costs primarily consist of those costs incurred in operating and staffing our North America and International segments’ fulfillment centers, customer service centers, and physical stores, including costs attributable to buying, receiving, inspecting, and warehousing inventories; picking, packaging, and preparing customer orders for shipment; payment processing and related transaction costs, including costs associated with our guarantee for certain seller transactions; responding to inquiries from customers; and supply chain management for our manufactured electronic devices. Fulfillment costs also include amounts paid to third parties that assist us in fulfillment and customer service operations.

Marketing

Marketing costs primarily consist of targeted online advertising, payroll and related expenses for personnel engaged in marketing and selling activities, and television advertising. We pay commissions to third parties when their customer referrals result in sales. We also participate in cooperative advertising arrangements with certain of our vendors, and other third parties.

Advertising and other promotional costs to market our products and services are expensed as incurred and were $5.0 billion, $6.3 billion, and $8.2 billion in 2016, 2017, and 2018. Prepaid advertising costs were not significant as of December 31, 2017 and 2018.

Technology and Content

Technology and content costs include payroll and related expenses for employees involved in the research and development of new and existing products and services, development, design, and maintenance of our stores, curation and display of products and services made available in our online stores, and infrastructure costs. Infrastructure costs include servers, networking equipment, and data center related depreciation, rent, utilities, and other expenses necessary to support AWS and other Amazon businesses. Collectively, these costs reflect the investments we make in order to offer a wide variety of products and services to our customers. Technology and content costs are generally expensed as incurred.

General and Administrative

General and administrative expenses primarily consist of payroll and related expenses; facilities and equipment expenses, such as depreciation expense and rent; professional fees and litigation costs; and other general corporate costs for corporate functions, including accounting, finance, tax, legal, and human resources, among others.

Stock-Based Compensation

Compensation cost for all stock awards expected to vest is measured at fair value on the date of grant and recognized over the service period. The fair value of restricted stock units is determined based on the number of shares granted and the quoted price of our common stock. Such value is recognized as expense over the service period, net of estimated forfeitures, using the accelerated method. The estimated number of stock awards that will ultimately vest requires judgment, and to the extent actual results or updated estimates differ from our current estimates, such amounts will be recorded as a cumulative adjustment in the period estimates are revised. We consider many factors when estimating expected forfeitures, including historical forfeiture experience and employee level.

Other Operating Expense, Net

Other operating expense, net, consists primarily of marketing-related, contract-based, and customer-related intangible asset amortization expense, and expenses related to legal settlements.

Other Income (Expense), Net

Other income (expense), net, consists primarily of foreign currency gains (losses) of $21 million, $247 million, and $(206) million in 2016, 2017, and 2018 and equity warrant valuation gains (losses) of $67 million, $109 million, and $(131) million in 2016, 2017, and 2018 and equity securities gains of $1 million, $18 million, and $145 million in 2016, 2017, and 2018.

Income Taxes

Income tax expense includes U.S. (federal and state) and foreign income taxes. Certain foreign subsidiary earnings are subject to U.S. taxation under the U.S. Tax Act, which also repeals U.S. taxation on the subsequent repatriation of those earnings. We intend to invest substantially all of our foreign subsidiary earnings, as well as our capital in our foreign subsidiaries, indefinitely outside of the U.S. in those jurisdictions in which we would incur significant, additional costs upon repatriation of such amounts.

Deferred income tax balances reflect the effects of temporary differences between the carrying amounts of assets and liabilities and their tax bases and are stated at enacted tax rates expected to be in effect when taxes are actually paid or recovered.

Deferred tax assets are evaluated for future realization and reduced by a valuation allowance to the extent we believe they will not be realized. We consider many factors when assessing the likelihood of future realization of our deferred tax assets, including our recent cumulative loss experience and expectations of future earnings, capital gains and investment in such jurisdiction, the carry-forward periods available to us for tax reporting purposes, and other relevant factors.

We utilize a two-step approach to recognizing and measuring uncertain income tax positions (tax contingencies). The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates it is more likely than not the position will be sustained on audit, including resolution of related appeals or litigation processes. The second step is to measure the tax benefit as the largest amount which is more than 50% likely of being realized upon ultimate settlement. We consider many factors when evaluating our tax positions and estimating our tax benefits, which may require periodic adjustments and which may not accurately forecast actual outcomes. We include interest and penalties related to our tax contingencies in income tax expense.

Fair Value of Financial Instruments

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.

For our cash, cash equivalents, or marketable securities, 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, or marketable securities categorized as Level 3 assets as of December 31, 2017 and 2018.

As part of entering into commercial agreements, we often obtain equity warrant assets giving us the right to acquire stock of other companies. As of December 31, 2017 and 2018, these warrants had a fair value of $441 million and $440 million, and are recorded within “Other assets” on our consolidated balance sheets. The related gain (loss) recorded in “Other income (expense), net” was $67 million, $109 million, and $(131) million in 2016, 2017, and 2018. These assets are primarily classified as Level 2 assets.

Cash and Cash Equivalents

We classify all highly liquid instruments with an original maturity of three months or less as cash equivalents.

Inventories

Inventories, consisting of products available for sale, are primarily accounted for using the first-in, first-out method, and are valued at the lower of cost and net realizable value. This valuation requires us to make judgments, based on currently available information, about the likely method of disposition, such as through sales to individual customers, returns to product vendors, or liquidations, and expected recoverable values of each disposition category.

We provide Fulfillment by Amazon services in connection with certain of our sellers’ programs. Third-party sellers maintain ownership of their inventory, regardless of whether fulfillment is provided by us or the third-party sellers, and therefore these products are not included in our inventories.

We also purchase electronic device components from a variety of suppliers and use several contract manufacturers to provide manufacturing services for our products. During the normal course of business, in order to manage manufacturing lead times and help ensure adequate supply, we enter into agreements with contract manufacturers and suppliers for certain electronic device components. A portion of our reported purchase commitments arising from these agreements consists of firm, non-cancellable commitments. These commitments are based on forecasted customer demand. If we reduce these commitments, we may incur additional costs. We also have firm, non-cancellable commitments for certain products offered in our Whole Foods Market stores.

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 2018, customer receivables, net, were $6.4 billion and $9.4 billion, vendor receivables, net, were $2.6 billion and $3.2 billion, and seller receivables, net, were $692 million and $710 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 $237 million, $348 million, and $495 million as of December 31, 2016, 2017, and 2018. Additions to the allowance were $451 million, $626 million, and $878 million, and deductions to the allowance were $403 million, $515 million, and $731 million in 2016, 2017, and 2018.

Software Development Costs

We incur software development costs related to products to be sold, leased, or marketed to external users, internal-use software, and our websites. Software development costs capitalized were not significant for the years presented. All other costs, including those related to design or maintenance, are expensed as incurred.

Property and Equipment, Net

Property and equipment are stated at cost less accumulated depreciation. Incentives that we receive from property and equipment vendors are recorded as a reduction in our costs. Property includes buildings and land that we own, along with property we have acquired under build-to-suit, finance, and capital lease arrangements. Equipment includes assets such as servers and networking equipment, heavy equipment, and other fulfillment equipment. Depreciation is recorded on a straight-line basis over the estimated useful lives of the assets (generally the lesser of 40 years or the remaining life of the underlying building, three years for our servers, five years for networking equipment, ten years for heavy equipment, and three to seven years for other fulfillment equipment). Depreciation expense is classified within the corresponding operating expense categories on our consolidated statements of operations.

Leases and Asset Retirement Obligations

We categorize leases at their inception as either operating or capital leases. On certain of our lease agreements, we may receive rent holidays and other incentives provided by the landlord. We recognize lease costs on a straight-line basis without regard to deferred payment terms, such as rent holidays, that defer the commencement date of required payments. Additionally, incentives we receive are treated as a reduction of our costs over the term of the agreement. Leasehold improvements are capitalized at cost and amortized over the lesser of their expected useful life or the non-cancellable term of the lease.

We establish assets and liabilities for the estimated construction costs incurred under build-to-suit lease arrangements to the extent we are involved in the construction of structural improvements or take construction risk prior to commencement of a lease. Upon occupancy of facilities under build-to-suit leases, we assess whether these arrangements qualify for sales recognition under the sale-leaseback accounting guidance. If we continue to be the deemed owner, the facilities are accounted for as finance leases.

We establish assets and liabilities for the present value of estimated future costs to retire long-lived assets at the termination or expiration of a lease. Such assets are depreciated over the lease period into operating expense, and the recorded liabilities are accreted to the future value of the estimated retirement costs.

As disclosed in “Accounting Pronouncements Not Yet Adopted,” our accounting for build-to-suit and finance leases will change on January 1, 2019.

Goodwill

We evaluate goodwill for impairment annually or more frequently when an event occurs or circumstances change that indicate the carrying value may not be recoverable. In testing goodwill for impairment, we may elect to utilize a qualitative assessment to evaluate whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If our qualitative assessment indicates that goodwill impairment is more likely than not, we perform a two-step impairment test. We test goodwill for impairment under the two-step impairment test by first comparing the book value of net assets to the fair value of the reporting units. If the fair value is determined to be less than the book value or qualitative factors indicate that it is more likely than not that goodwill is impaired, a second step is performed to compute the amount of impairment as the difference between the estimated fair value of goodwill and the carrying value. We estimate the fair value of the reporting units using discounted cash flows. Forecasts of future cash flows are based on our best estimate of future net sales and operating expenses, based primarily on expected category expansion, pricing, market segment share, and general economic conditions.

We completed the required annual testing of goodwill for impairment for all reporting units as of April 1, 2018, and determined that goodwill is not impaired as the fair value of our reporting units substantially exceeded their book value. There were no events that caused us to update our annual impairment test. See “Note 4 — Acquisitions, Goodwill, and Acquired Intangible Assets.”

Other Assets

Included in “Other assets” on our consolidated balance sheets are amounts primarily related to acquired intangible assets, net of accumulated amortization; video and music content, net of accumulated amortization; long-term deferred tax assets; certain equity investments; marketable securities restricted for longer than one year, the majority of which are attributable to collateralization of bank guarantees and debt related to our international operations; and equity warrant assets.

Video and Music Content

We obtain video and music content for customers through licensing agreements that have a wide range of licensing provisions, which include both fixed and variable payment schedules. When the license fee for a specific movie, television, or music title is determinable or reasonably estimable and the content is available for streaming, we recognize an asset representing the fee and a corresponding liability for the amounts owed. We relieve the liability as payments are made and we amortize the asset to “Cost of sales” on a straight-line basis or on an accelerated basis, based on estimated usage patterns, which typically ranges from one to five years. If we are unable to reasonably estimate the cost per title, no asset or liability is recorded and licensing costs are expensed as incurred. We also develop original content. Capitalized production costs associated with our original content are limited by the amount of revenue we expect to earn, which results in a portion being expensed as incurred. These capitalized costs are amortized to “Cost of sales” on an accelerated basis that follows the viewing pattern of customer streams in the first months after availability.

Investments

We generally invest our excess cash in AAA-rated money market funds and investment grade short- to intermediate-term fixed income securities. Such investments are included in “Cash and cash equivalents” or “Marketable securities” on the accompanying consolidated balance sheets. Marketable debt securities are classified as available-for-sale and reported at fair value with unrealized gains and losses included in “Accumulated other comprehensive loss.”

Equity investments are accounted for using the equity method of accounting if the investment gives us the ability to exercise significant influence, but not control, over an investee. Equity-method investments are included within “Other assets” on our consolidated balance sheets. Our share of the earnings or losses as reported by equity-method investees, amortization of basis differences, and related gains or losses, if any, are classified as “Equity-method investment activity, net of tax” on our consolidated statements of operations.

Equity investments without readily determinable fair values and for which we do not have the ability to exercise significant influence are accounted for at cost with adjustments for observable changes in prices or impairments and are classified as “Other assets” on our consolidated balance sheets.

Equity investments that have readily determinable fair values are included in “Marketable securities” on our consolidated balance sheets and measured at fair value with changes recognized in “Other income (expense), net” on our consolidated statement of operations.

We periodically evaluate whether declines in fair values of our investments indicate impairment. For debt securities and equity method investments, we also evaluate whether declines in fair value of our investments below their book value are other-than-temporary. This evaluation consists of several qualitative and quantitative factors regarding the severity and duration of the unrealized loss as well as our ability and intent to hold the investment until a forecasted recovery occurs. Additionally, we assess whether we have plans to sell the security or it is more likely than not we will be required to sell any investment before recovery of its amortized cost basis. Factors considered include: quoted market prices; recent financial results and operating trends; implied values from any recent transactions or offers of investee securities; credit quality of debt instrument issuers; other publicly available information that may affect the value of our investments; duration and severity of the decline in value; and our strategy and intentions for holding the investment.

Long-Lived Assets

Long-lived assets, other than goodwill, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets might not be recoverable. Conditions that would necessitate an impairment assessment include a significant decline in the observable market value of an asset, a significant change in the extent or manner in which an asset is used, or any other significant adverse change that would indicate that the carrying amount of an asset or group of assets may not be recoverable.

For long-lived assets used in operations, impairment losses are only recorded if the asset’s carrying amount is not recoverable through its undiscounted, probability-weighted future cash flows. We measure the impairment loss based on the difference between the carrying amount and estimated fair value. Long-lived assets are considered held for sale when certain criteria are met, including when management has committed to a plan to sell the asset, the asset is available for sale in its immediate condition, and the sale is probable within one year of the reporting date. Assets held for sale are reported at the lower of cost or fair value less costs to sell. Assets held for sale were not significant as of December 31, 2017 and 2018.

Accrued Expenses and Other

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

As of December 31, 2017 and 2018, our liabilities for payroll related expenses were $2.9 billion and $3.4 billion and our liabilities for unredeemed gift cards were $3.0 billion and $2.8 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.

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 AWS services and Amazon Prime memberships. Our total unearned revenue as of December 31, 2017 was $6.1 billion, of which $5.3 billion was recognized as revenue during the year ended December 31, 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 $1.4 billion of unearned revenue as of December 31, 2017 and 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, those commitments not yet recognized were $19.3 billion as of December 31, 2018. The weighted average remaining life of our long-term contracts is 3.3 years. However, the amount and timing of revenue recognition is largely driven by customer usage, which can extend beyond the original contractual term.

Foreign Currency

We have internationally-focused stores for which the net sales generated, as well as most of the related expenses directly incurred from those operations, are denominated in local functional currencies. The functional currency of our subsidiaries that either operate or support these stores is generally the same as the local currency. Assets and liabilities of these subsidiaries are translated into U.S. Dollars at period-end foreign exchange rates, and revenues and expenses are translated at average rates prevailing throughout the period. Translation adjustments are included in “Accumulated other comprehensive loss,” a separate component of stockholders’ equity, and in the “Foreign currency effect on cash and cash equivalents,” on our consolidated statements of cash flows. Transaction gains and losses including intercompany transactions denominated in a currency other than the functional currency of the entity involved are included in “Other income (expense), net” on our consolidated statements of operations. In connection with the settlement and remeasurement of intercompany balances, we recorded gains (losses) of $62 million, $202 million, and $(186) million in 2016, 2017, and 2018.

Accounting Pronouncements Recently Adopted

In May 2014, the Financial Accounting Standards Board (“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. Prior year amounts have not been adjusted and continue to be reported in accordance with our historic accounting policy.

The impact of applying this ASU for the year ended December 31, 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 $3.8 billion. Service sales also increased by approximately $3.0 billion for the year ended December 31, 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):



Year Ended December 31, 2016	Previously Reported			Adjustments			As Revised
Operating activities	$	17,272		$	(69	)	$	17,203
Investing activities	(9,876		)	360			(9,516		)
Financing activities	(3,740		)	24			(3,716		)
Net change in cash, cash equivalents, and restricted cash	$	3,656		$	315		$	3,971



Year Ended December 31, 2017	Previously Reported			Adjustments			As Revised
Operating activities	$	18,434		$	(69	)	$	18,365
Investing activities	(27,819		)	735			(27,084		)
Financing activities	9,860			68			9,928
Net change in cash, cash equivalents, and restricted cash	$	475		$	734		$	1,209

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 an immaterial cumulative adjustment to retained earnings rather than retrospectively adjusting prior periods. This adoption approach will result in a balance sheet presentation that will not be comparable to the prior period in the first year of adoption. The adoption of this ASU will result in the recognition of operating lease assets and liabilities of approximately $21 billion, which includes the reclassification of finance leases to operating leases of approximately $1.2 billion, and the derecognition of build-to-suit lease assets and liabilities when we do not control the building during the construction period of approximately $1.5 billion.