Cognizant Technology Solutions (CTSH) 10-K 27 Feb 18 2017 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2017	Feb. 22, 2018	Jun. 30, 2017
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Trading Symbol	CTSH
Entity Registrant Name	COGNIZANT TECHNOLOGY SOLUTIONS CORP
Entity Central Index Key	1,058,290
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		588,051,333
Entity Well-known Seasoned Issuer	Yes
Entity Public Float			$ 39
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No

Consolidated Statements Of Fina

Consolidated Statements Of Financial Position - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Assets
Cash and cash equivalents	$ 1,925	$ 2,034
Short-term investments	3,131	3,135
Trade accounts receivable, net of allowances of $65 and $48, respectively	2,865	2,556
Unbilled accounts receivable	357	349
Other current assets	833	526
Total current assets	9,111	8,600
Property and equipment, net	1,324	1,311
Goodwill	2,704	2,554
Intangible assets, net	981	951
Deferred income tax assets, net	418	425
Long-term Investments	235	62
Other noncurrent assets	448	359
Total assets	15,221	14,262
Liabilities and Stockholders' Equity
Accounts payable	210	175
Deferred revenue	383	306
Short-term debt	175	81
Accrued expenses and other current liabilities	2,071	1,856
Total current liabilities	2,839	2,418
Deferred revenue, noncurrent	104	151
Deferred income tax liabilities, net	146	6
Long-term debt	698	797
Long-term income taxes payable	584	0
Other noncurrent liabilities	181	162
Total liabilities	4,552	3,534
Commitments and contingencies (See Note 14)
Stockholders' Equity:
Preferred stock, $0.10 par value, 15.0 shares authorized, none issued	0	0
Class A common stock, $0.01 par value, 1,000 shares authorized, 588 and 608 shares issued and outstanding at December 31, 2017 and 2016, respectively	6	6
Additional paid-in capital	49	358
Retained earnings	10,544	10,478
Accumulated other comprehensive income (loss)	70	(114)
Total stockholders’ equity	10,669	10,728
Total liabilities and stockholders’ equity	$ 15,221	$ 14,262

Consolidated Statements Of Fin3

Consolidated Statements Of Financial Position (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Trade accounts receivable, allowances	$ 65	$ 48
Preferred stock, par value	$ 0.10	$ 0.10
Preferred stock, shares authorized	15,000,000	15,000,000
Preferred stock, issued	0	0
Class A common stock, par value	$ 0.01	$ 0.01
Class A common stock, shares authorized	1,000,000,000	1,000,000,000
Class A common stock, shares issued	588,000,000	608,000,000
Class A common stock, shares outstanding	588,000,000	608,000,000

Consolidated Statements Of Oper

Consolidated Statements Of Operations - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Revenues	$ 14,810	$ 13,487	$ 12,416
Operating expenses:
Cost of revenues (exclusive of depreciation and amortization expense shown separately below)	9,152	8,108	7,440
Selling, general and administrative expenses	2,769	2,731	2,509
Depreciation and amortization expense	408	359	325
Income from operations	2,481	2,289	2,142
Other income (expense), net:
Interest income	133	115	84
Interest expense	(23)	(19)	(18)
Foreign currency exchange gains (losses), net	67	(30)	(43)
Other, net	(3)	2	(1)
Total other income (expense), net	174	68	22
Income before provision for income taxes	2,655	2,357	2,164
Provision for income taxes	(1,153)	(805)	(540)
Income from equity method investments	2	1	0
Net income	$ 1,504	$ 1,553	$ 1,624
Basic earnings per share	$ 2.54	$ 2.56	$ 2.67
Diluted earnings per share	$ 2.53	$ 2.55	$ 2.65
Weighted average number of common shares outstanding—Basic	593	607	609
Dilutive effect of shares issuable under stock-based compensation plans	2	3	4
Weighted average number of common shares outstanding—Diluted	595	610	613
Dividends declared per common share	$ 0.45	$ 0	$ 0

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 1,504	$ 1,553	$ 1,624
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	111	(59)	(55)
Change in unrealized gains and losses on cash flow hedges, net of taxes	76	51	75
Change in unrealized losses on available-for-sale investment securities, net of taxes	(3)	0	(3)
Other comprehensive income (loss)	184	(8)	17
Comprehensive income	$ 1,688	$ 1,545	$ 1,641

Consolidated Statements Of Stoc

Consolidated Statements Of Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated other comprehensive income (loss):
AOCI, beginning balance at Dec. 31, 2014	$ 7,740	$ 6	$ 556	$ 7,301	$ (123)
Beginning balance, shares at Dec. 31, 2014		609
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,624			1,624
Other comprehensive income	17				17
Common stock issued, stock-based compensation plans	131		131
Common stock issued, stock based compensation plans and other, shares		7
Tax benefit, stock-based compensation plans	34		34
Stock-based compensation expense	192		192
Repurchases of common stock	460		460
Repurchases of common stock, shares		(7)
AOCI, ending balance at Dec. 31, 2015	9,278	$ 6	453	8,925	(106)
Ending balance, shares at Dec. 31, 2015		609
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,553			1,553
Other comprehensive income	(8)				(8)
Common stock issued, stock-based compensation plans	176		176
Common stock issued, stock based compensation plans and other, shares		8
Tax benefit, stock-based compensation plans	24		24
Stock-based compensation expense	217		217
Repurchases of common stock	512		512
Repurchases of common stock, shares		(9)
AOCI, ending balance at Dec. 31, 2016	$ 10,728	$ 6	358	10,478	(114)
Ending balance, shares at Dec. 31, 2016	608	608
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 1,504			1,504
Other comprehensive income	184				184
Common stock issued, stock-based compensation plans	189		189
Common stock issued, stock based compensation plans and other, shares		9
Stock-based compensation expense	221		221
Repurchases of common stock	1,889		719	1,170
Repurchases of common stock, shares		(29)
Dividends	(268)			(268)
AOCI, ending balance at Dec. 31, 2017	$ 10,669	$ 6	$ 49	$ 10,544	$ 70
Ending balance, shares at Dec. 31, 2017	588	588

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities:
Net income	$ 1,504	$ 1,553	$ 1,624
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	443	379	330
Provision for doubtful accounts	15	12	10
Deferred income taxes	124	(91)	(126)
Stock-based compensation expense	221	217	192
Other	(86)	46	49
Changes in assets and liabilities:
Trade accounts receivable	(249)	(330)	(322)
Other current assets	(181)	(104)	(33)
Other noncurrent assets	(89)	(59)	(39)
Accounts payable	16	6	19
Deferred revenue, current and noncurrent	18	(38)	50
Other current and noncurrent liabilities	671	54	433
Net cash provided by operating activities	2,407	1,645	2,187
Cash flows from investing activities:
Purchases of property and equipment	(284)	(300)	(273)
Purchases of available-for-sale investment securities	(3,120)	(4,231)	(2,050)
Proceeds from maturity or sale of available-for-sale investment securities	3,404	3,982	1,290
Purchases of held-to-maturity investment securities	(1,221)	(54)	0
Proceeds from maturity of held-to-maturity investment securities	404	15	0
Purchases of other investments	(385)	(884)	(954)
Proceeds from maturity or sale of other investments	836	843	618
Payments for business combinations, net of cash acquired, and equity and cost method investments	(216)	(334)	(2)
Net cash (used in) investing activities	(582)	(963)	(1,371)
Cash flows from financing activities:
Issuance of common stock under stock-based compensation plans	189	176	131
Repurchases of common stock	(1,889)	(512)	(460)
Repayment of term loan borrowings and capital lease obligations	(95)	(57)	(53)
Net change in notes outstanding under the revolving credit facility	75	(350)	(300)
Dividends paid	(265)	0	0
Net cash (used in) financing activities	(1,985)	(743)	(682)
Effect of exchange rate changes on cash and cash equivalents	51	(30)	(19)
(Decrease) increase in cash and cash equivalents	(109)	(91)	115
Cash and cash equivalents, beginning of year	2,034	2,125	2,010
Cash and cash equivalents, end of period	1,925	2,034	2,125
Supplemental information:
Cash paid for income taxes during the year	587	845	579
Cash interest paid during the year	$ 21	$ 16	$ 14

Business Description and Summar

Business Description and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Business Description and Summary of Significant Accounting Policies	Business Description and Summary of Significant Accounting Policies The terms “Cognizant,” “we,” “our,” “us” and “the Company” refer to Cognizant Technology Solutions Corporation and its subsidiaries unless the context indicates otherwise. Description of Business. We are one of the world’s leading professional services companies. We are in business to help our customers adapt, compete and grow in the face of continual shifts and disruptions within their markets. We do so by partnering with them to apply technology to transform their business, operating and technology models allowing them to achieve the full value of digitizing their entire enterprises. We call this being “digital at scale.” When implemented, it enables customers to achieve more efficient and effective operations while reshaping their business models for innovation and growth. Our industry-based, consultative approach helps customers envision, build and run more innovative and efficient businesses. Our core competencies include: business, process, operations and technology consulting, application development and systems integration, enterprise information management, application testing, application maintenance, information technology, or IT, infrastructure services, and business process services. We tailor our services and solutions to specific industries and use an integrated global delivery model that employs customer service teams based at customer locations and delivery teams located at dedicated global and regional delivery centers. Basis of Presentation, Principles of Consolidation and Use of Estimates. The consolidated financial statements are presented in accordance with generally accepted accounting principles in the United States of America, or GAAP, and reflect the consolidated financial position, results of operations, comprehensive income and cash flows of our consolidated subsidiaries for all periods presented. All intercompany balances and transactions have been eliminated in consolidation. The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying disclosures. We evaluate our estimates on a continuous basis. We base our estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances. The actual amounts may vary from the estimates used in the preparation of the accompanying consolidated financial statements. We have reclassified certain prior period amounts to conform to current period presentation. Cash and Cash Equivalents and Investments. Cash and cash equivalents consist of all cash balances, including money market funds and liquid instruments. Liquid instruments are classified as cash equivalents when their maturities at the date of purchase are 90 days or less and as short-term investments when their maturities at the date of purchase are greater than 90 days. We determine the appropriate classification of our investments in marketable securities at the date of purchase and reevaluate such designation at each balance sheet date. We have classified and accounted for our marketable securities as either trading, available-for-sale or held-to-maturity. After consideration of our risk versus reward objectives, as well as our liquidity requirements, we may sell our trading and available-for-sale securities prior to their stated maturities. We classify these marketable securities with maturities at the date of purchase beyond 90 days as short-term investments based on their highly liquid nature and because such marketable securities represent an investment of cash that is available for current operations. Our held-to-maturity investment securities are financial instruments for which we have the intent and ability to hold to maturity and we classify these securities with maturities beyond 90 days but less than one year as short-term investments. Any held-to-maturity investment securities with maturities beyond one year from the balance sheet date are classified as noncurrent. Trading securities are reported at fair value with changes in unrealized gains and losses recorded in Other income (expense), net in our consolidated statements of operations. Available-for-sale securities are reported at fair value with changes in unrealized gains and losses recorded as a separate component of accumulated other comprehensive income (loss) until realized. We determine the cost of the securities sold based on the specific identification method. Held-to-maturity securities are reported at amortized cost. Time deposits with financial institutions are valued at cost, which approximates fair value. Interest and amortization of premiums and discounts for debt securities are included in interest income. On a quarterly basis, we evaluate our available-for-sale and held-to-maturity investments for possible other-than-temporary impairment by reviewing quantitative and qualitative factors. If we do not intend to sell the security or it is not more likely than not that we will be required to sell the security before recovery of our amortized cost, we evaluate quantitative and qualitative criteria to determine whether we expect to recover the amortized cost basis of the security. If we do not expect to recover the entire amortized cost basis of the security, we consider the security to be other-than-temporarily impaired and we record the difference between the security’s amortized cost basis and its recoverable amount in earnings and the difference between the security’s recoverable amount and fair value in other comprehensive income. If we intend to sell the security or it is more likely than not that we will be required to sell the security before recovery of its amortized cost basis, the security is also considered other-than-temporarily impaired and we recognize the entire difference between the security’s amortized cost basis and its fair value in earnings. Allowance for Doubtful Accounts. We maintain an allowance for doubtful accounts for estimated losses resulting from the inability of our customers to make required payments. The allowance for doubtful accounts is determined by evaluating the relative credit-worthiness of each customer, historical collections experience and other information, including the aging of the receivables. We evaluate the collectibility of our accounts receivable on an on-going basis and write off accounts when they are deemed to be uncollectible. Unbilled Accounts Receivable. Unbilled accounts receivable represent revenues recognized that are to be billed in subsequent periods, as per the terms of the related contracts. Short-term Financial Assets and Liabilities. Cash and certain cash equivalents, trade receivables, accounts payable and other accrued liabilities are short-term in nature and, accordingly, their carrying values approximate fair value. Property and Equipment. Property and equipment are stated at cost, net of accumulated depreciation. Depreciation is calculated on a straight-line basis over the estimated useful lives of the assets. Leasehold improvements are amortized on a straight-line basis over the shorter of the term of the lease or the estimated useful life of the improvement. In India, leasehold land is leased by us from the government of India with lease terms ranging up to 99 years. Lease payments are made at the inception of the lease agreement and amortized over the lease term. Maintenance and repairs are expensed as incurred, while renewals and betterments are capitalized. Deposits paid towards acquisition of long-lived assets and the cost of assets not put in use before the balance sheet date are disclosed under the caption “Capital work-in-progress” in Note 6 . Internal Use Software. We capitalize certain costs that are incurred to purchase, develop and implement internal-use software during the application development phase, which primarily include coding, testing and certain data conversion activities. Capitalized costs are amortized on a straight-line basis over the useful life of the software. Costs incurred in performing activities associated with the preliminary project phase and the post-implementation phase are expensed as incurred. Software to be Sold, Leased or Marketed. We capitalize costs incurred after technological feasibility is reached but before software is available for general release to customers, which primarily include coding and testing activities. Once the product is ready for general release, capitalized costs are amortized over the useful life of the software. Business Combinations. We account for business combinations using the acquisition method, which requires the identification of the acquirer, the determination of the acquisition date and the allocation of the purchase price paid by the acquirer to the identifiable tangible and intangible assets acquired, the liabilities assumed, including any contingent consideration and any noncontrolling interest in the acquiree at their acquisition date fair values. Goodwill represents the excess of the purchase price over the fair value of net assets acquired, including the amount assigned to identifiable intangible assets. Identifiable intangible assets with finite lives are amortized over their useful lives. Acquisition-related costs are expensed in the periods in which the costs are incurred. The results of operations of acquired businesses are included in our consolidated financial statements from the acquisition date . Equity Method Investments. Equity investments that give us the ability to exercise significant influence, but not control, over an investee are accounted for using the equity method of accounting and recorded in the caption "Long-term investments" on our consolidated statements of financial position. Equity method investments are initially recorded at cost and any excess cost over our proportionate share of the fair value of the net assets of the investee at the acquisition date is recognized as goodwill and included in the carrying amount of the investment. We periodically review the carrying value of our equity method investments to determine if there has been an other-than-temporary decline in carrying value. The Company's proportionate share of the net income or loss of the investee is recorded in the caption "Income from equity method investments" on our consolidated statements of operations. The investment balance is increased or decreased for cash contributions or distributions to or from these investees. If we subsequently obtain control of the investee, the existing carrying value of the investment is remeasured to the fair value on the change of control date and any gain or loss is recognized in results of operations. Cost Method Investments. Equity investments without readily determinable fair values in which we do not exercise significant influence or control are accounted for using the cost method of accounting and recorded in the caption "Long-term investments" on our consolidated statements of financial position. Investments are carried at cost and are adjusted only for other-than-temporary declines in fair value, certain distributions and additional investments. We periodically review the carrying value of our cost method investments to determine if there has been an other-than-temporary decline in carrying value. Long-lived Assets and Finite-lived Intangibles. We review long-lived assets and certain finite-lived identifiable intangibles for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. We recognize an impairment loss when the sum of undiscounted expected future cash flows is less than the carrying amount of such assets. The impairment loss is determined as the amount by which the carrying amount of the asset exceeds the fair value of the asset. Intangible assets consist primarily of customer relationships and developed technology, which are being amortized on a straight-line basis over their estimated useful lives. Goodwill and Indefinite-lived Intangibles. We evaluate goodwill and indefinite-lived intangible assets for impairment at least annually, or as circumstances warrant. Goodwill is evaluated at the reporting unit level by comparing the fair value of the reporting unit with its carrying amount including goodwill. An impairment of goodwill exists if the carrying amount of the reporting unit exceeds its fair value. The impairment loss is the amount by which the carrying amount exceeds the reporting unit’s fair value, limited to the total amount of goodwill allocated to that reporting unit. For indefinite-lived intangible assets, if our annual qualitative assessment indicates that it is more-likely-than-not that an indefinite-lived intangible asset is impaired, we test the assets for impairment by comparing the fair value of such assets to their carrying value. If an impairment is indicated, a write down to the fair value of indefinite-lived intangible asset is recorded. Stock Repurchase Program. Under the Board of Directors authorized stock repurchase program, the Company is authorized to repurchase its Class A common stock through open market purchases, including under a trading plan adopted pursuant to Rule 10b5-1 of the Exchange Act, or in private transactions, including through accelerated stock repurchase agreements (or ASRs) entered into with financial institutions, in accordance with applicable federal securities laws. We account for the repurchased shares as constructively retired. Shares are returned to the status of authorized and unissued shares at the time of repurchase or in the periods they are delivered, if repurchased under an ASR. To reflect share repurchases in the consolidated statement of financial position, the Company (i) reduces common stock for the par value of the shares, (ii) reduces additional paid-in capital for the amount in excess of par during the period in which the shares are repurchased and (iii) records any residual amount in excess of available additional paid-in capital to retained earnings. Upfront payments related to ASRs are accounted for as a reduction to stockholders’ equity in the consolidated statement of financial position in the period the payments are made. Revenue Recognition. Revenues related to time-and-materials contracts are recognized as the service is performed and amounts are earned. Revenues from transaction- or volume-based priced contracts are recognized as transactions are processed and amounts are earned. Revenues related to fixed-price contracts for highly complex application development and systems integration services are recognized as the service is performed using the percentage of completion method of accounting, under which the total value of revenues is recognized on the basis of the percentage that each contract’s total labor cost to date bears to the total expected labor costs (cost to cost method). Revenues related to fixed-price outsourcing services are recognized on a straight-line basis unless revenues are earned and obligations are fulfilled in a different pattern. Revenues related to fixed-price contracts for consulting or other technology services are recognized as services are performed on a proportional performance basis based upon the level of effort. For all services, revenues are earned and recognized only when all of the following criteria are met: evidence of an arrangement exists, the price is fixed or determinable, the services have been rendered and collectibility is reasonably assured. Contingent or incentive revenues are recognized when the contingency is satisfied and we conclude the amounts are earned. Volume discounts are recorded as a reduction of revenues as services are provided. Revenues also include the reimbursement of out-of-pocket expenses. Costs to deliver services are expensed as incurred with the exception of specific costs directly related to transition or set-up activities for outsourcing contracts. Transition costs are deferred and expensed ratably over the period of service. Deferred amounts are protected by collected cash or early termination penalty clauses and are monitored regularly for impairment. Impairment losses are recorded when projected remaining undiscounted operating cash flows of the related contract are not sufficient to recover the carrying amount of the contract assets. Deferred transition costs were approximately $ 267 million and $ 188 million as of December 31, 2017 and 2016 , respectively, and are included in other noncurrent assets in our consolidated statements of financial position. Costs related to warranty provisions are accrued at the time the related revenues are recorded. We may enter into arrangements that consist of multiple elements. Such arrangements may include any combination of our products, solutions and services. For arrangements with multiple deliverables, we evaluate at the inception of each new arrangement all deliverables to determine whether they represent separate units of accounting. For arrangements with multiple units of accounting, other than arrangements that contain software licenses and software-related services, we allocate consideration among the units of accounting, where separable, based on their relative selling price. Relative selling price is determined based on vendor-specific objective evidence, or VSOE, if it exists. Otherwise, third-party evidence of selling price is used, when it is available, and in circumstances when neither VSOE nor third-party evidence of selling price is available, management’s best estimate of selling price is used. Revenues are recognized for each unit of accounting based on our revenue recognition policy described above. Fixed-price contracts are generally cancelable subject to a specified notice period. All services provided by us through the date of cancellation are due and payable under the contract terms. We issue invoices related to fixed-price contracts based upon achievement of milestones during a project or other contractual terms. Differences between the timing of billing, based on contract milestones or other contractual terms, and the recognition of revenues are recognized as either unbilled receivables or deferred revenue. Estimates of certain fixed-price contracts are subject to adjustment as a project progresses to reflect changes in expected completion costs or efforts. The cumulative impact of any revision in estimates is reflected in the financial reporting period in which the change in estimate becomes known and any anticipated losses on contracts are recognized immediately. We also generate product revenues from licensing our software. For perpetual software license arrangements that do not require significant modification or customization of the underlying software, revenues are recognized when the software is delivered and all other software revenue recognition criteria are met. For software license arrangements that require significant functionality enhancements or modification of the software, revenues for the software license and those services are recognized as those services are performed. For software license arrangements that include a right to use the product for a defined period of time, we recognize revenues ratably over the term of the license. We may enter into arrangements with customers that purchase both software licenses and software-related services from us at the same time, or within close proximity of one another (referred to as software-related multiple-element arrangements). Such software related multiple-element arrangements may include software licenses, software license updates, product support contracts and other software-related services. For those software related multiple-element arrangements, we apply the residual method to determine the amount of software license revenues. Under the residual method, if VSOE of fair value exists for undelivered elements in a multiple-element arrangement, revenues equal to the fair value of the undelivered elements are deferred with the remaining portion of the arrangement consideration generally recognized upon delivery of the software license. For arrangements in which VSOE of fair value does not exist for each software-related undelivered element, revenues for the software license are deferred and not recognized until VSOE of fair value is available for the undelivered element or delivery of each element has occurred. If the only undelivered element is a service, revenues from the delivered element are recognized over the service period. We also enter into multiple-element arrangements that may include a combination of software licenses and various software-related and non-software-related services. In such arrangements, we first allocate the total arrangement consideration, based on relative selling prices, between the software group of elements and the non-software group of elements. We then further allocate consideration within the software group to the respective elements within that group following the software-related multiple-element arrangements policies described above. For the non-software group of elements, we further allocate consideration to the respective elements based on relative selling prices. After the arrangement consideration has been allocated to the individual elements, we account for each respective element in the arrangement as described above. Stock-Based Compensation. Stock-based compensation expense for awards of equity instruments to employees and non-employee directors is determined based on the grant-date fair value of those awards. We recognize these compensation costs net of an estimated forfeiture rate over the requisite service period of the award. Forfeitures are estimated on the date of grant and revised if actual or expected forfeiture activity differs materially from original estimates. Foreign Currency. The assets and liabilities of our foreign subsidiaries whose functional currency is not the U.S. dollar are translated into U.S. dollars from functional currencies at current exchange rates while revenues and expenses are translated from functional currencies at average monthly exchange rates. The resulting translation adjustments are recorded in the caption "Accumulated other comprehensive income (loss)" on the accompanying consolidated statements of financial position. Foreign currency transactions and balances are those that are denominated in a currency other than the subsidiary’s functional currency. The U.S. dollar is the functional currency for certain foreign subsidiaries who conduct business predominantly in U.S. dollars. For these subsidiaries, transactions and balances denominated in the local currency are foreign currency transactions. Foreign currency transactions and balances related to non-monetary assets and liabilities are remeasured to the functional currency of the subsidiary at historical exchange rates while monetary assets and liabilities are remeasured to the functional currency of the subsidiary at current exchange rates. Foreign currency exchange gains or losses from remeasurement are included in the caption "Foreign currency exchange gain (losses), net" on our consolidated statement of operations together with gains or losses on our undesignated foreign currency hedges. Derivative Financial Instruments. Derivative financial instruments are recorded on the balance sheet as either an asset or liability measured at its fair value as of the reporting date. Our derivative financial instruments consist of foreign exchange forward contracts. For derivative financial instruments to qualify for hedge accounting, the following criteria must be met: (1) the hedging instrument must be designated as a hedge; (2) the hedged exposure must be specifically identifiable and must expose us to risk; and (3) it must be expected that a change in fair value of the derivative financial instrument and an opposite change in the fair value of the hedged exposure will have a high degree of correlation. Changes in our derivatives’ fair values are recognized in income unless specific hedge accounting and documentation criteria are met (i.e., the instruments are designated and accounted for as hedges). We record the effective portion of the unrealized gains and losses on our derivative financial instruments that are designated as cash flow hedges in the caption "Accumulated other comprehensive income (loss)" in the accompanying consolidated statements of financial position. Any ineffectiveness or excluded portion of a designated cash flow hedge is recognized in income. Upon occurrence of the hedged transaction, the gains and losses on the derivative are recognized in income. Income Taxes. We provide for income taxes utilizing the asset and liability method of accounting. Under this method, deferred income taxes are recorded to reflect the tax consequences in future years of differences between the tax basis of assets and liabilities and their financial reporting amounts at each balance sheet date, based on enacted tax laws and statutory tax rates applicable to the periods in which the differences are expected to affect taxable income. If it is determined that it is more likely than not that future tax benefits associated with a deferred income tax asset will not be realized, a valuation allowance is provided. The effect of a change in tax rates on deferred income tax assets and liabilities is recognized in the provision for income taxes in the period that includes the enactment date. Beginning in 2017, differences between actual tax benefits realized on employee stock awards and estimated tax benefits at date of grant are adjusted to our provision for income taxes upon vesting or exercise of the stock award. Our provision for income taxes also includes the impact of provisions established for uncertain income tax positions, as well as any related penalties and interest. Earnings Per Share, or EPS. Basic EPS excludes dilution and is computed by dividing earnings available to common stockholders by the weighted-average number of common shares outstanding for the period. Diluted EPS includes all potential dilutive common stock in the weighted average shares outstanding. For purposes of computing diluted earnings per share for the years ended December 31, 2017 , 2016 and 2015 , respectively, 2 million, 3 million and 4 million shares were assumed to have been outstanding related to common share equivalents. We exclude from the calculation of diluted EPS options with exercise prices that are greater than the average market price and shares related to stock-based awards whose combined exercise price and unamortized fair value were greater in each of those periods than the average market price of our common stock for the period, because their effect would be anti-dilutive. We excluded less than 1 million of anti-dilutive shares in each of 2017 , 2016 and 2015 from our diluted EPS calculation. We include performance stock unit awards in the dilutive potential common shares when they become contingently issuable per the authoritative guidance and exclude the awards when they are not contingently issuable. Recently Adopted Accounting Pronouncements. Date Issued and Topic Date Adopted and Method Description Impact March 2016 Derivatives and Hedging January 1, 2017 Prospectively This update clarifies the effect of derivative contract novations on existing hedge accounting relationships. As it relates to derivative instruments, novation refers to replacing one of the parties to a derivative instrument with a new party, which may occur for a variety of reasons such as: financial institution mergers, intercompany transactions, an entity exiting a particular derivatives business or relationship, or because of laws or regulatory requirements. The update clarifies that a change in the counterparty to a derivative instrument that has been designated as the hedging instrument does not, in and of itself, require dedesignation of that hedge accounting relationship provided that all other hedge accounting criteria continue to be met. The adoption of this update did not have any effect on our financial condition or results of operations. March 2016 January 1, 2017 Prospectively / Retrospectively This update requires excess tax benefits and tax deficiencies to be recorded to the provision for income taxes in the income statement when the awards vest or are exercised and provides an accounting policy election to account for forfeitures as they occur. The update also clarifies that all cash payments made on an employee’s behalf for withheld shares should be presented as financing activity in the statement of cash flows and cash flows related to excess tax benefits should be classified along with other income tax cash flows as an operating activity. The primary impact of the adoption of this update is that we prospectively reduced our 2017 provision for income taxes and earning per share by $40 million or $0.07, respectively, for the recognition of net excess income tax benefits rather than an increase to additional paid-in capital. We elected to continue to estimate expected forfeitures to determine the stock compensation expense to be recognized each period. We also elected to retrospectively apply the presentation requirements for cash flows related to excess tax benefits for all periods presented, which resulted in an increase to both net cash provided by operating activities and net cash used in financing activities of $24 million and $34 million during 2016 and 2015, respectively. January 2017 Business Combinations January 1, 2017 Prospectively This update clarifies the definition of a business and requires a business to include at least an input and a substantive process that together significantly contribute to the ability to create outputs. The update also states that the definition of a business is not met if substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets. The adoption of this update did not have a material effect on our financial condition or results of operations. January 2017 Goodwill January 1, 2017 Prospectively This update eliminates the need to calculate the implied fair value of goodwill when an impairment is indicated. The update states that goodwill impairment is measured as the excess of a reporting unit’s carrying value over its fair value, not to exceed the carrying amount of goodwill. The adoption of this update did not have any effect on our financial condition or results of operations. New Accounting Pronouncements. Date Issued and Topic Effective Date Description Impact May 2014 January 1, 2018 The new standard, as amended, sets forth a single comprehensive model for recognizing and reporting revenues. The standard also requires additional financial statement disclosures that will enable users to understand the nature, amount, timing and uncertainty of revenues and cash flows relating to customer contracts. The standard allows for two methods of adoption: the full retrospective adoption, which requires the standard to be applied to each prior period presented, or the modified retrospective adoption, which requires the cumulative effect of adoption to be recognized as an adjustment to opening retained earnings in the period of adoption. We will adopt the standard using the modified retrospective method. The most significant impacts of the new standard primarily relate to (1) changes in the method used to measure progress on our application maintenance, consulting and business process services fixed-price contracts, (2) the longer period of amortization for costs to fulfill a contract, as well as (3) the timing of revenue recognition and allocation of purchase price on our software license contracts. We expect the one-time adjustment to opening retained earnings in connection with the adoption of this standard to be an increase of approximately $119 million, after a tax impact of approximately $36 million. February 2016 January 1, 2019 The new standard replaces the existing guidance on leases and requires the lessee to recognize a right-of-use asset and a lease liability for all leases with lease terms equal to or greater than twelve months. For finance leases, the lessee would recognize interest expense and amortization of the right-of-use asset, and for operating leases, the lessee would recognize total lease expense on a straight-line basis. Upon adoption, entities will be required to use a modified retrospective transition which

Internal Investigation and Rela

Internal Investigation and Related Matters	12 Months Ended
	Dec. 31, 2017
Internal Investigation and Related Matters [Abstract]
Internal Investigation and Related Matters	Internal Investigation and Related Matters We are conducting an internal investigation focused on whether certain payments relating to Company-owned facilities in India were made improperly and in possible violation of the U.S. Foreign Corrupt Practices Act, or FCPA, and other applicable laws. The investigation is also examining various other payments made in small amounts in India that may not have complied with Company policy or applicable law. In September 2016, we voluntarily notified the U.S. Department of Justice, or DOJ, and Securities and Exchange Commission, or SEC, and are cooperating fully with both agencies. The investigation is being conducted under the oversight of the Audit Committee, with the assistance of outside counsel. To date, the investigation has identified a total of approximately $6 million in payments made between 2009 and 2016 that may have been improper. During the year ended December 31, 2016, we recorded out-of-period corrections related to $4 million of such payments that had been previously capitalized that should have been expensed. Of the $4 million out-of-period correction, $3 million was recorded in the third quarter of 2016 and $1 million was recorded in the fourth quarter of 2016. These out-of-period corrections and the other $2 million in potentially improper payments were not material to any previously issued financial statements. There were no adjustments recorded during the year ended December 31, 2017.

Business Combinations

Business Combinations	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Business Combinations	Business Combinations All acquisitions completed during the three years ended December 31, 2017, 2016 and 2015 were not individually material to our operations, financial position or cash flow. Accordingly, pro forma results have not been presented. These acquisitions were included in our consolidated financial statements as of the date on which the businesses were acquired. We have allocated the purchase price related to these transactions to tangible and intangible assets and liabilities, including non-deductible goodwill, based on their estimated fair values. 2017 In 2017, we completed five business combinations for total consideration of approximately $233 million , inclusive of contingent consideration. These acquisitions included (a) an intelligent products and solutions company based in Japan specializing in digital strategy, product design and engineering, the internet of things, and enterprise mobility that expands our digital transformation portfolio and capabilities, (b) a U.S. healthcare management consulting firm that strengthens our consulting service offerings within the healthcare consulting market, (c) a leading national provider of business process services to the U.S. government healthcare market that further strengthens our business process-as-a-service solutions for government and public health programs, (d) a provider of digital experience and marketing solutions for some of the world's most recognized brands and an independent Adobe partner in Europe that will enhance our ability to deliver business critical digital experience solutions, and (e) an independent full-service digital agency in the UK specializing in customer experience, digital strategy, technology and content creation that will enhance and expand our digital interactive expertise in experience design, human science-driven insights and analytics. 2016 In 2016, we completed eight business combinations for total consideration of approximately $287 million . These transactions included (a) an acquisition of a global consulting and technology services company that strengthens and expands our digital capabilities to deliver cloud-based application services, (b) three acquisitions of delivery centers spanning several industries such as oil and gas services, steel and metal products, and banking and insurance to enhance our delivery capabilities across Europe along with multi-year service agreements, (c) an acquisition of tangible property, an assembled workforce and a multi-year service agreement which qualifies as a business combination under accounting guidance, (d) an acquisition of a global consulting company that offers digital innovation, strategy, design and technology services, (e) an acquisition of a digital marketing and customer experience agency that expands our digital business capabilities across Europe, and (f) an acquisition of an Australia-based consulting, business transformation and technology services provider in the insurance industry. 2015 We did not complete any significant business combinations in 2015. Allocation of Purchase Price The allocations of purchase price to the fair value of the aggregate assets acquired and liabilities assumed were as follows: 2017 2016 Fair Value Weighted Average Useful Life Fair Value Weighted Average Useful Life (in millions) (in millions) Cash $ 8 $ 17 Current assets 47 84 Property, plant and equipment and other noncurrent assets 19 53 Non-deductible goodwill 125 157 Customer relationship intangible assets 147 10.6 years 199 6.6 years Other intangible assets 4 2.4 years 1 3.3 years Current liabilities (50 ) (173 ) Noncurrent liabilities (67 ) (51 ) Purchase price $ 233 $ 287 For acquisitions completed in 2017, the allocation is preliminary and will be finalized as soon as practicable within the measurement period, but in no event later than one year following the date of acquisition. The primary items that generated goodwill are the value of the acquired assembled workforces and synergies between the acquired companies and us, neither of which qualify as an amortizable intangible asset.

Realignment Charges

Realignment Charges	12 Months Ended
	Dec. 31, 2017
Realignment Charges [Abstract]
Realignment Charges	Realignment Charges In 2017, we began a realignment of our business to accelerate the shift to digital services and solutions while improving the overall efficiency of our operations. During 2017, we incurred $72 million in realignment charges, reported in "Selling, general and administrative expenses" in our consolidated statements of operations. The realignment charges are comprised of severance costs, including those related to a voluntary separation program, or VSP, advisory fees related to non-routine shareholder matters and to the development of our realignment and return of capital programs and lease termination costs. Realignment charges for the year ended December 31, 2017 were as follows: (in millions) Employee separations $ 53 Advisory fees 18 Lease termination costs 1 Total realignment costs $ 72 There were no realignment charges incurred in 2016 and 2015.

Investments

Investments	12 Months Ended
	Dec. 31, 2017
Investments [Abstract]
Investments	Investments Our investments were as follows as of December 31: 2017 2016 (in millions) Short-term investments: Trading investment securities $ 25 $ 25 Available-for-sale investment securities 1,972 2,264 Held-to-maturity investment securities 745 40 Time deposits 389 806 Total short-term investments $ 3,131 $ 3,135 Long-term investments: Equity and cost method investments $ 74 $ 62 Held-to-maturity investment securities 161 — Total long-term investments $ 235 $ 62 Trading Investment Securities Our trading investment securities consist of a U.S. dollar denominated investment in a fixed income mutual fund. Unrealized losses recognized on our trading investment securities were $1 million in each of the years ended December 31, 2017 and 2016. There were no realized gains or losses on trading securities during the years ended December 31, 2017 and 2016. The value of the fixed income mutual fund invested in fixed income securities is based on the net asset value, or NAV, of the fund, with appropriate consideration of the liquidity and any restrictions on disposition of our investment in the fund. Available-for-Sale Investment Securities Our available-for-sale investment securities consist of U.S. dollar denominated investments primarily in U.S. Treasury notes, U.S. government agency debt securities, municipal debt securities, non-U.S. government debt securities, U.S. and international corporate bonds, certificates of deposit, commercial paper, debt securities issued by supranational institutions, and asset-backed securities, including securities backed by auto loans, credit card receivables, and other receivables. Our investment guidelines are to purchase securities which are investment grade at the time of acquisition. We monitor the credit ratings of the securities in our portfolio on an ongoing basis. The amortized cost, gross unrealized gains and losses and fair value of our available-for-sale investment securities were as follows at December 31: 2017 Amortized Cost Unrealized Gains Unrealized Losses Fair Value (in millions) U.S. Treasury and agency debt securities $ 667 $ — $ (6 ) $ 661 Corporate and other debt securities 439 — (2 ) 437 Certificates of deposit and commercial paper 450 — — 450 Asset-backed securities 297 — (2 ) 295 Municipal debt securities 130 — (1 ) 129 Total available-for-sale investment securities $ 1,983 $ — $ (11 ) $ 1,972 2016 Amortized Cost Unrealized Gains Unrealized Losses Fair Value (in millions) U.S. Treasury and agency debt securities $ 605 $ — $ (3 ) $ 602 Corporate and other debt securities 407 — (2 ) 405 Certificates of deposit and commercial paper 910 1 — 911 Asset-backed securities 232 — (1 ) 231 Municipal debt securities 116 — (1 ) 115 Total available-for-sale investment securities $ 2,270 $ 1 $ (7 ) $ 2,264 The fair value and related unrealized losses of our available-for-sale investment securities in a continuous unrealized loss position for less than 12 months and for 12 months or longer were as follows as of December 31: 2017 Less than 12 Months 12 Months or More Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in millions) U.S. Treasury and agency debt securities $ 519 $ (4 ) $ 124 $ (2 ) $ 643 $ (6 ) Corporate and other debt securities 297 (1 ) 126 (1 ) 423 (2 ) Certificates of deposit and commercial paper 49 — — — 49 — Asset-backed securities 193 (1 ) 94 (1 ) 287 (2 ) Municipal debt securities 107 (1 ) 18 — 125 (1 ) Total $ 1,165 $ (7 ) $ 362 $ (4 ) $ 1,527 $ (11 ) 2016 Less than 12 Months 12 Months or More Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in millions) U.S. Treasury and agency debt securities $ 526 $ (3 ) $ — $ — $ 526 $ (3 ) Corporate and other debt securities 342 (2 ) 1 — 343 (2 ) Certificates of deposit and commercial paper 185 — — — 185 — Asset-backed securities 206 (1 ) 1 — 207 (1 ) Municipal debt securities 88 (1 ) 1 — 89 (1 ) Total $ 1,347 $ (7 ) $ 3 $ — $ 1,350 $ (7 ) The unrealized losses for the above securities as of December 31, 2017 and 2016 are primarily attributable to changes in interest rates. At each reporting date, the Company performs an evaluation of impaired available-for-sale securities to determine if the unrealized losses are other-than-temporary. As of December 31, 2017 , we do not consider any of the investments to be other-than-temporarily impaired. The gross unrealized gains and losses in the above tables were recorded, net of tax, in "Accumulated other comprehensive income (loss)" in our consolidated statements of financial position. The contractual maturities of our fixed income available-for-sale investment securities as of December 31, 2017 are set forth in the following table: Amortized Cost Fair Value (in millions) Due within one year $ 590 $ 590 Due after one year up to two years 454 450 Due after two years up to three years 556 551 Due after three years 86 86 Asset-backed securities 297 295 Total available-for-sale investment securities $ 1,983 $ 1,972 Asset-backed securities were excluded from the maturity categories because the actual maturities may differ from the contractual maturities since the underlying receivables may be prepaid without penalties. Further, actual maturities of debt securities may differ from those presented above since certain obligations provide the issuer the right to call or prepay the obligation prior to scheduled maturity without penalty. Proceeds from sales of available-for-sale investment securities and the gross gains and losses that have been included in earnings as a result of those sales were as follows: 2017 2016 2015 (in millions) Proceeds from sales of available-for-sale investment securities $ 2,922 $ 3,541 $ 782 Gross gains $ 1 $ 5 $ 1 Gross losses (3 ) (4 ) — Net realized (losses) gains on sales of available-for-sale investment securities $ (2 ) $ 1 $ 1 Held-to-Maturity Investment Securities Our held-to-maturity investment securities consist of Indian rupee denominated investments primarily in commercial paper, international corporate bonds and government debt securities. Our investment guidelines are to purchase securities that are investment grade at the time of acquisition. We monitor the credit ratings of the securities in our portfolio on an ongoing basis. The amortized cost, gross unrealized gains and losses and fair value of held-to-maturity investment securities were as follows at December 31: 2017 Amortized Unrealized Unrealized Fair (in millions) Short-term investments: Corporate and other debt securities $ 346 $ — $ (1 ) $ 345 Commercial paper 399 — (2 ) 397 Total short-term held-to-maturity investments 745 — (3 ) 742 Long-term investments: Corporate and other debt securities 161 — (1 ) 160 Total held-to-maturity investment securities $ 906 $ — $ (4 ) $ 902 2016 Amortized Unrealized Unrealized Fair (in millions) Short-term investments: Certificates of deposit and commercial paper $ 40 $ — $ — $ 40 There were no long-term held-to-maturity investment securities at December 31, 2016. The fair value and related unrealized losses of held-to-maturity investment securities in a continuous unrealized loss position for less than 12 months and for 12 months or longer were as follows as of December 31, 2017 : Less than 12 Months 12 Months or More Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in millions) Corporate and other debt securities $ 473 $ (2 ) $ — $ — $ 473 $ (2 ) Commercial paper 394 (2 ) — — 394 (2 ) Total $ 867 $ (4 ) $ — $ — $ 867 $ (4 ) As of December 31, 2016, there were no material held-to-maturity investment securities in an unrealized loss position. At each reporting date, the Company performs an evaluation of held-to-maturity securities to determine if the unrealized losses are other-than-temporary. We do not consider any of the investments to be other-than-temporarily impaired as of December 31, 2017 . The contractual maturities of our fixed income held-to-maturity investment securities as of December 31, 2017 are set forth in the following table: Amortized Cost Fair Value (in millions) Due within one year $ 745 $ 742 Due after one year up to two years 155 154 Due after two years 6 6 Total held-to-maturity investment securities $ 906 $ 902 During the years ended December 31, 2017 and 2016, there were no transfers of investments between our trading, available-for-sale and held-to-maturity investment portfolios. Equity and Cost Method Investments As of December 31, 2017 and 2016, we had equity method investments of $67 million and $57 million , respectively, which primarily consist of a 49% ownership interest in a strategic consulting firm specializing in the use of human sciences to help business leaders better understand customer behavior. As of December 31, 2017 and 2016, we had cost method investments of $7 million and $5 million , respectively.

Property and Equipment, net

Property and Equipment, net	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment, Net [Abstract]
Property and Equipment, net	Property and Equipment, net Property and equipment were as follows as of December 31: Estimated Useful Life (Years) 2017 2016 (in millions) Buildings 30 $ 836 $ 823 Computer equipment 3 – 5 364 379 Computer software 3 – 8 594 470 Furniture and equipment 5 – 9 511 431 Land 19 23 Leasehold land lease term 63 63 Capital work-in-progress 145 169 Leasehold improvements Shorter of the lease term or the life of the leased asset 308 266 Sub-total 2,840 2,624 Accumulated depreciation and amortization (1,516 ) (1,313 ) Property and equipment, net $ 1,324 $ 1,311 Depreciation and amortization expense related to property and equipment was $313 million, $266 million and $233 million for the years ended December 31, 2017 , 2016 and 2015 , respectively. The gross amount of property and equipment recorded under capital leases was $44 million and $37 million at December 31, 2017 and 2016, respectively, and primarily related to buildings. Accumulated amortization and amortization expense related to capital lease assets were immaterial for the periods presented. Amortization expense of leasehold land is immaterial for the periods presented and is included in depreciation and amortization expense in our accompanying consolidated statements of operations. The amount of property and equipment recorded for software to be sold, leased or marketed, net of accumulated amortization was $40 million and $33 million as of December 31, 2017 and 2016, respectively. Amortization expense of property and equipment recorded for software to be sold, leased or marketed was immaterial for the periods presented.

Goodwill and Intangible Assets,

Goodwill and Intangible Assets, net	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets, net	Goodwill and Intangible Assets, net Changes in goodwill by our reportable segments were as follows for the years ended December 31, 2017 and 2016 : Segment January 1, 2017 Goodwill Additions and Adjustments Foreign Currency Translation Adjustments December 31, 2017 (in millions) Financial Services $ 227 $ 27 $ 11 $ 265 Healthcare 2,089 13 4 2,106 Products and Resources (1) 159 72 9 240 Communications, Media and Technology (2) 79 11 3 93 Total goodwill $ 2,554 $ 123 $ 27 $ 2,704 Segment January 1, 2016 Goodwill Additions and Adjustments Foreign Currency Translation Adjustments December 31, 2016 (in millions) Financial Services $ 203 $ 28 $ (4 ) $ 227 Healthcare 2,076 14 (1 ) 2,089 Products and Resources (1) 67 94 (2 ) 159 Communications, Media and Technology (2) 59 21 (1 ) 79 Total goodwill $ 2,405 $ 157 $ (8 ) $ 2,554 _____________ (1) Products and Resources was previously referred to as Manufacturing/Retail/Logistics. (2) Communications, Media and Technology was previously referred to as Other. We have not recognized any impairment losses on our goodwill balances to-date. Components of intangible assets were as follows as of December 31: 2017 Gross Carrying Amount Accumulated Amortization Net Carrying Amount (in millions) Customer relationships $ 1,005 $ (304 ) $ 701 Developed technology 333 (140 ) 193 Indefinite life trademarks 63 — 63 Other 51 (27 ) 24 Total intangible assets $ 1,452 $ (471 ) $ 981 2016 Gross Carrying Amount Accumulated Amortization Net Carrying Amount (in millions) Customer relationships $ 845 $ (219 ) $ 626 Developed technology 332 (96 ) 236 Indefinite life trademarks 63 — 63 Other 48 (22 ) 26 Total intangible assets $ 1,288 $ (337 ) $ 951 Other than certain trademarks with indefinite lives, our intangible assets have finite lives and, as such, are subject to amortization. Amortization of intangible assets totaled $130 million for 2017 , $113 million for 2016 and $97 million for 2015 . Of these amounts, during 2017 , 2016 and 2015 , amortization of $35 million , $20 million and $5 million, respectively, relating to customer relationship intangible assets attributable to direct revenue contracts with sellers of acquired businesses was recorded as a reduction of revenues. Estimated amortization related to our existing intangible assets for the next five years is as follows: Year Amount (in millions) 2018 $ 134 2019 131 2020 123 2021 120 2022 105

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	12 Months Ended
	Dec. 31, 2017
Accrued Expenses And Other Current Liabilities [Abstract]
Accrued Expenses and Other Current Liabilities	Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities were as follows as of December 31: 2017 2016 (in millions) Compensation and benefits $ 1,272 $ 1,134 Income taxes 48 10 Professional fees 100 99 Travel and entertainment 32 36 Customer volume and other incentives 289 258 Derivative financial instruments 5 4 Other 325 315 Total accrued expenses and other current liabilities $ 2,071 $ 1,856

Debt

Debt	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Debt	Debt In 2014, we entered into a credit agreement with a commercial bank syndicate, or, as amended, the Credit Agreement, providing for a $1,000 million unsecured term loan and a $750 million unsecured revolving credit facility. All notes drawn to date under the revolving credit facility have been less than 90 days in duration. The term loan and the revolving credit facility both mature in November 2019. We are required under the Credit Agreement to make scheduled quarterly principal payments on the term loan. We were in compliance with all debt covenants and representations as of December 31, 2017. The Credit Agreement requires interest to be paid at either the base rate or the Eurocurrency rate, plus a margin. The margin over the base rate is 0.00% , and the margin over the Eurocurrency rate ranges from 0.75% to 1.125% , depending on our debt ratings (or, if we have not received debt ratings, from 0.875% to 1.00% , depending on our debt to total stockholders' equity ratio). Under the Credit Agreement, we are required to pay commitment fees on the unused portion of the revolving credit facility, which vary based on our debt ratings (or, if we have not received debt ratings, our debt to total stockholders' equity ratio). At December 31, 2017, the interest rate on the term loan was 2.4% . As the interest rates on our term loan and notes outstanding under the revolving credits facility are variable, the fair value of our debt balances approximates their carrying value as of December 31, 2017 and 2016. The Credit Agreement contains certain negative covenants, including limitations on liens, mergers, consolidations and acquisitions, subsidiary indebtedness and affiliate transactions, as well as certain affirmative covenants. In addition, the Credit Agreement requires us to maintain a debt to total stockholders' equity ratio not in excess of 0.40 to 1.00. Short-term Debt The following summarizes our short-term debt balances as of December 31: 2017 2016 Amount Weighted Average Interest Rate Amount Weighted Average Interest Rate (in millions) (in millions) Notes outstanding under revolving credit facility $ 75 4.5 % $ — — % Term loan - current maturities 100 2.4 % 81 1.8 % Total short-term debt $ 175 $ 81 Long-term Debt The following summarizes our long-term debt balances as of December 31: 2017 2016 (in millions) Term loan, due November 2019 $ 800 $ 881 Less: Current maturities (100 ) (81 ) Deferred financing costs (2 ) (3 ) Long-term debt, net of current maturities $ 698 $ 797 The following represents the schedule of maturities of our long-term debt: Year Amounts (in millions) 2018 $ 100 2019 700 $ 800

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income before provision for income taxes shown below is based on the geographic location to which such income is attributed for years ended December 31: 2017 2016 2015 (in millions) United States $ 810 $ 752 $ 739 Foreign 1,845 1,605 1,425 Income before provision for income taxes $ 2,655 $ 2,357 $ 2,164 The provision for income taxes consists of the following components for the years ended December 31: 2017 2016 2015 (in millions) Current: Federal and state $ 767 $ 544 $ 352 Foreign 262 352 314 Total current provision 1,029 896 666 Deferred: Federal and state 102 (44 ) (58 ) Foreign 22 (47 ) (68 ) Total deferred provision (benefit) 124 (91 ) (126 ) Total provision for income taxes $ 1,153 $ 805 $ 540 On December 22, 2017, the United States enacted the Tax Reform Act, which significantly revised the U.S. corporate income tax law for tax years beginning after December 31, 2017 by (among other provisions): • reducing the U.S. federal statutory corporate income tax rate from 35% to 21% for tax years beginning after December 31, 2017; • implementing a modified territorial tax system that includes a one-time transition tax on all accumulated undistributed earnings of foreign subsidiaries; and • providing for a full deduction on future dividends received from foreign affiliates. During the fourth quarter of 2017, in accordance with the SEC Staff Accounting Bulletin No. 118 - Income Tax Accounting Implications of the Tax Cuts and Jobs Act, we recorded a one-time provisional net income tax expense of $617 million , which is comprised of: (i) the one-time transition tax expense on accumulated undistributed earnings of foreign subsidiaries of $635 million , (ii) foreign and U.S. state income tax expense that will be applicable upon repatriation of the accumulated undistributed earnings of our foreign subsidiaries, other than our Indian subsidiaries, of $53 million , partially offset by (iii) an income tax benefit of $71 million resulting from the revaluation of U.S. net deferred income tax liabilities to the new lower U.S. income tax rate. The transition tax on undistributed earnings is payable over the next eight years, of which $51 million is payable within one year. The one-time incremental income tax expense is provisional as it reflects certain assumptions based upon our interpretation of the Tax Reform Act as of January 18, 2018 and may change, possibly materially, as we receive additional clarification and guidance and as the interpretation of the Tax Reform Act evolves over time. We anticipate completing the accounting for the Tax Reform Act within the measurement period. As a result of the enactment of the Tax Reform Act, our historical and future foreign earnings are no longer subject to U.S. federal income taxes upon repatriation, beyond the one-time transition tax. We therefore reevaluated our assertion that our foreign earnings would be indefinitely reinvested and concluded that our Indian earnings will continue to be indefinitely reinvested while historical accumulated undistributed earnings of our foreign subsidiaries, other than our Indian subsidiaries, are available for repatriation to the United States. Our assertion that our earnings in India continue to be indefinitely reinvested is consistent with our ongoing strategy to expand our Indian operations, including through infrastructure investments. As of December 31, 2017, the amount of unrepatriated Indian earnings is estimated at approximately $4,082 million . If such Indian earnings are repatriated in the future, or are no longer deemed to be indefinitely reinvested, then we would expect to accrue additional tax expense at a rate of approximately 21% of actual cash distributions to the United States, based on our current interpretation of India tax law. This estimate is subject to change based on tax legislation developments in India and other jurisdictions as well as judicial and interpretive developments of applicable tax laws. In May 2016, India enacted the Finance Bill 2016 that, among other things, expanded the applicability of India’s buyback distribution tax to certain share buyback transactions occurring after June 1, 2016. In mid-May, prior to the June 1, 2016 effective date of the enactment, our principal operating subsidiary in India repurchased shares from its shareholders, which are non-Indian Cognizant entities, valued at $ 2.8 billion. This transaction, or the India Cash Remittance, was undertaken pursuant to a plan approved by the High Court of Madras and simplified the shareholding structure of our principal operating subsidiary in India. Pursuant to the transaction, our principal Indian operating subsidiary repurchased approximately $ 1.2 billion of the total $ 2.8 billion of shares from its U.S. shareholders, resulting in incremental tax expense, while the remaining $ 1.6 billion was repurchased from its shareholder outside the United States. Net of taxes, the transaction resulted in a remittance of cash to the United States in the amount of $ 1.0 billion. As a result of this transaction, we incurred an incremental 2016 income tax expense of $ 238 million. The reconciliation between our effective income tax rate and the U.S. federal statutory rate were as follows for the years ended December 31: 2017 % 2016 % 2015 % (Dollars in millions) Tax expense, at U.S. federal statutory rate $ 929 35.0 $ 825 35.0 $ 757 35.0 State and local income taxes, net of federal benefit 39 1.5 42 1.8 42 2.0 Non-taxable income for Indian tax purposes (216 ) (8.2 ) (203 ) (8.6 ) (201 ) (9.3 ) Rate differential on foreign earnings (76 ) (2.9 ) (55 ) (2.3 ) (34 ) (1.6 ) Net impact related to the Tax Reform Act 617 23.2 — — — — India Cash Remittance — — 238 10.1 — — Recognition of previously unrecognized income tax benefits related to uncertain tax positions (73 ) (2.7 ) (16 ) (0.7 ) (23 ) (1.1 ) Credits and other incentives (37 ) (1.4 ) (57 ) (2.4 ) (23 ) (1.0 ) Other (30 ) (1.1 ) 31 1.3 22 1.0 Total provision for income taxes $ 1,153 43.4 $ 805 34.2 $ 540 25.0 The significant components of deferred income tax assets and liabilities recorded on the consolidated statements of financial position were as follows as of December 31: 2017 2016 (in millions) Deferred income tax assets: Net operating losses $ 15 $ 14 Revenue recognition 55 69 Compensation and benefits 125 165 Stock-based compensation 14 25 Minimum alternative tax (MAT) and other credits 369 274 Other accrued expenses 22 161 600 708 Less: valuation allowance (10 ) (10 ) Deferred income tax assets, net 590 698 Deferred income tax liabilities: Depreciation and amortization 209 266 Deferred costs 65 — Other 44 13 Deferred income tax liabilities 318 279 Net deferred income tax assets $ 272 $ 419 In the table above, certain unrecognized income tax benefits have been netted against available same-jurisdiction deferred income tax carryforward assets. At December 31, 2017 , we had foreign and U.S. net operating loss carryforwards of approximately $38 million and $12 million, respectively. We have recorded valuation allowances on certain foreign net operating loss carryforwards. As of December 31, 2017 and 2016 , deferred income tax assets related to the minimum alternative tax, or MAT, were approximately $278 million and $286 million, respectively. The calculation of the MAT includes all profits realized by our Indian subsidiaries and any MAT paid is creditable against future corporate income tax, subject to certain limitations. Our existing MAT assets expire between March 2023 and March 2032 and we expect to fully utilize them within the applicable expiration periods, which was extended to 15 years from 10 years by the 2017 Union Budget of India. Our Indian subsidiaries, collectively referred to as Cognizant India, are primarily export-oriented and are eligible for certain income tax holiday benefits granted by the government of India for export activities conducted within Special Economic Zones, or SEZs, for periods of up to 15 years . Our SEZ income tax holiday benefits are currently scheduled to expire in whole or in part during the years 2018 to 2026 and may be extended on a limited basis for an additional five years per unit if certain reinvestment criteria are met. Our Indian profits ineligible for SEZ benefits are subject to corporate income tax at the rate of 34.6% . In addition, all Indian profits, including those generated within SEZs, are subject to the MAT, at the rate of 21.3% . For the years ended December 31, 2017 , 2016 and 2015 , the effect of the income tax holidays granted by the Indian government was to reduce the overall income tax provision and increase net income by approximately $217 million, $203 million and $201 million, respectively, and increase diluted EPS by $0.36 , $0.33 and $0.33 , respectively. Any MAT paid is creditable against future Indian corporate income tax, subject to limitations. We conduct business globally and file income tax returns in the United States, including federal and state, as well as various foreign jurisdictions. Tax years that remain subject to examination by the Internal Revenue Service are 2012 and onward, and years that remain subject to examination by state authorities vary by state. Years under examination by foreign tax authorities are 2001 and onward. We record incremental tax expense, based upon the more-likely-than-not standard, for any uncertain tax positions. In addition, when applicable, we adjust the previously recorded income tax expense to reflect examination results when the position is effectively settled or otherwise resolved. Our ongoing evaluations of the more-likely-than-not outcomes of the examinations and related tax positions require judgment and can result in adjustments that increase or decrease our effective income tax rate, as well as impact our operating results. The specific timing of when the resolution of each tax position will be reached is uncertain. Changes in unrecognized income tax benefits were as follows for the years ended December 31: 2017 2016 (in millions) Balance, beginning of year $ 151 $ 139 Additions based on tax positions related to the current year 17 11 Additions for tax positions of prior years 2 19 Additions for tax positions of acquired subsidiaries — — Reductions for tax positions due to lapse of statutes of limitations (41 ) (15 ) Reductions for tax positions of prior years (32 ) (1 ) Settlements — — Foreign currency exchange movement — (2 ) Balance, end of year $ 97 $ 151 At December 31, 2017 , the unrecognized income tax benefits would affect our effective income tax rate, if recognized. While the Company believes uncertain tax positions may be settled or resolved within the next twelve months, it is difficult to estimate the income tax impact of these potential resolutions at this time. We recognize accrued interest and any penalties associated with uncertain tax positions as part of our provision for income taxes. The total amount of accrued interest and penalties at December 31, 2017 and 2016 was approximately $8 million and $7 million, respectively, and relates to U.S. and foreign tax matters. The amounts of interest and penalties recorded in the provision for income taxes in 2017 , 2016 and 2015 were immaterial.

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments In the normal course of business, we use foreign exchange forward contracts to manage foreign currency exchange rate risk. The estimated fair value of the foreign exchange forward contracts considers the following items: discount rate, timing and amount of cash flow and counterparty credit risk. Derivatives may give rise to credit risks from the possible non-performance by counterparties. Credit risk is limited to the fair value of those contracts that are favorable to us. We have limited our credit risk by entering into derivative transactions only with highly-rated financial institutions, limiting the amount of credit exposure with any one financial institution and conducting ongoing evaluation of the creditworthiness of the financial institutions with which we do business. In addition, all the assets and liabilities related to our foreign exchange forward contracts set forth in the below table are subject to International Swaps and Derivatives Association, or ISDA, master netting arrangements or other similar agreements with each individual counterparty. These master netting arrangements generally provide for net settlement of all outstanding contracts with the counterparty in the case of an event of default or a termination event. We have presented all the assets and liabilities related to our foreign exchange forward contracts on a gross basis, with no offsets, in our accompanying consolidated statements of financial position. There is no financial collateral (including cash collateral) posted or received by us related to our foreign exchange forward contracts. The following table provides information on the location and fair values of derivative financial instruments included in our consolidated statement of financial position as of December 31: 2017 2016 Designation of Derivatives Location on Statement of Financial Position Assets Liabilities Assets Liabilities (in millions) Foreign exchange forward contracts - Designated as cash flow hedging instruments Other current assets $ 134 $ — $ 34 $ — Other noncurrent assets 20 — 17 — Total 154 — 51 — Foreign exchange forward contracts - Not designated as cash flow hedging instruments Accrued expenses and other current liabilities — 5 — 4 Total — 5 — 4 Total $ 154 $ 5 $ 51 $ 4 Cash Flow Hedges We have entered into a series of foreign exchange forward contracts that are designated as cash flow hedges of Indian rupee denominated payments in India. These contracts are intended to partially offset the impact of movement of exchange rates on future operating costs and are scheduled to mature each month during 2018 and 2019 . Under these contracts, we purchase Indian rupees and sell U.S. dollars. The changes in fair value of these contracts are initially reported in the caption “Accumulated other comprehensive income (loss)” in our consolidated statements of financial position and are subsequently reclassified to earnings in the same period the forecasted Indian rupee denominated payments are recorded in earnings. As of December 31, 2017 , we estimate that $100 million, net of tax, of the net gains related to derivatives designated as cash flow hedges recorded in accumulated other comprehensive income (loss) is expected to be reclassified into earnings within the next 12 months. The notional value of our outstanding contracts by year of maturity and the net unrealized gains included in accumulated other comprehensive income (loss) for such contracts were as follows as of December 31: 2017 2016 (in millions) 2017 $ — $ 1,320 2018 1,185 1,020 2019 720 — Total notional value of contracts outstanding $ 1,905 $ 2,340 Net unrealized gains included in accumulated other comprehensive income (loss), net of taxes $ 115 $ 39 Upon settlement or maturity of the cash flow hedge contracts, we record the related gains or losses, based on our designation at the commencement of the contract, with the related hedged Indian rupee denominated expense reported within cost of revenues and selling, general and administrative expenses. Hedge ineffectiveness was immaterial for all periods presented. The following table provides information on the location and amounts of pre-tax gains on our cash flow hedges for the year ended December 31: Change in Derivative Gains Recognized in Accumulated Other Comprehensive Income (Loss) (effective portion) Location of Net Derivative Gains Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (effective portion) Net Gains Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (effective portion) 2017 2016 2017 2016 (in millions) Foreign exchange forward contracts - Designated as cash flow hedging instruments $ 232 $ 83 Cost of revenues $ 109 $ 14 Selling, general and administrative expenses 20 3 Total $ 129 $ 17 The activity related to the change in net unrealized gains on our cash flow hedges included in accumulated other comprehensive income (loss) is presented in Note 13 . Other Derivatives We use foreign exchange forward contracts, which have not been designated as hedges, to hedge balance sheet exposure to certain monetary assets and liabilities denominated in currencies other than the functional currency of our foreign subsidiaries. We entered into a series of foreign exchange forward contracts that are scheduled to mature in 2018. Realized gains or losses and changes in the estimated fair value of these derivative financial instruments are reported in the caption "Foreign currency exchange gains (losses), net" in our consolidated statements of operations. Additional information related to our outstanding foreign exchange forward contracts not designated as hedging instruments is as follows as of December 31: 2017 2016 Notional Market Value Notional Market Value (in millions) Contracts outstanding $ 255 $ (5 ) $ 213 $ (4 ) The following table provides information on the location and amounts of realized and unrealized pre-tax gains and losses on our other derivative financial instruments for the year ended December 31: Location of Net (Losses) on Derivative Instruments Amount of Net (Losses) on Derivative Instruments 2017 2016 (in millions) Foreign exchange forward contracts - Not designated as hedging instruments Foreign currency exchange gains (losses), net $ (23 ) $ (3 ) The related cash flow impacts of all of our derivative activities are reflected as cash flows from operating activities.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements We measure our cash equivalents, investments and foreign exchange forward contracts at fair value. The authoritative guidance defines fair value as the exit price, or the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants as of the measurement date. The authoritative guidance also establishes a fair value hierarchy that is intended to increase consistency and comparability in fair value measurements and related disclosures. The fair value hierarchy is based on inputs to valuation techniques that are used to measure fair value that are either observable or unobservable. Observable inputs reflect assumptions market participants would use in pricing an asset or liability based on market data obtained from independent sources while unobservable inputs reflect a reporting entity’s pricing based upon their own market assumptions. The fair value hierarchy consists of the following three levels: • Level 1 – Inputs are quoted prices in active markets for identical assets or liabilities. • Level 2 – Inputs are quoted prices for similar assets or liabilities in an active market, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable and market-corroborated inputs which are derived principally from or corroborated by observable market data. • Level 3 – Inputs are derived from valuation techniques in which one or more significant inputs or value drivers are unobservable. The following table summarizes our financial assets and (liabilities) measured at fair value on a recurring basis as of December 31, 2017 : Level 1 Level 2 Level 3 Total (in millions) Cash equivalents: Money market funds $ 334 $ — $ — $ 334 Bank deposits — 80 — 80 Commercial paper — 386 — 386 Total cash equivalents 334 466 — 800 Short-term investments: Time deposits — 389 — 389 Available-for-sale investment securities: U.S. Treasury and agency debt securities 585 76 — 661 Corporate and other debt securities — 437 — 437 Certificates of deposit and commercial paper — 450 — 450 Asset-backed securities — 295 — 295 Municipal debt securities — 129 — 129 Total available-for-sale investment securities 585 1,387 — 1,972 Held-to-maturity investment securities: Commercial paper — 397 — 397 Corporate and other debt securities — 345 — 345 Total short-term held-to-maturity investment securities — 742 — 742 Total short-term investments (1) 585 2,518 — 3,103 Long-term investments: Held-to-maturity investment securities: Corporate and other debt securities — 160 — 160 Total long-term held-to-maturity investment securities — 160 — 160 Total long-term investments (2) — 160 — 160 Derivative financial instruments - foreign exchange forward contracts: Other current assets — 134 — 134 Accrued expenses and other current liabilities — (5 ) — (5 ) Other noncurrent assets — 20 — 20 Total $ 919 $ 3,293 $ — $ 4,212 ________________ (1) Excludes trading securities invested in a mutual fund valued at $25 million based on the NAV of the fund at December 31, 2017. (2) Excludes equity and cost method investments of $74 million at December 31, 2017, which are accounted for using the equity method of accounting and at cost, respectively. The following table summarizes our financial assets and (liabilities) measured at fair value on a recurring basis as of December 31, 2016 : Level 1 Level 2 Level 3 Total (in millions) Cash equivalents: Money market funds $ 624 $ — $ — $ 624 Commercial paper — 131 — 131 Total cash equivalents 624 131 — 755 Short-term investments: Time deposits — 806 — 806 Available-for-sale investment securities: U.S. Treasury and agency debt securities 558 44 — 602 Corporate and other debt securities — 405 — 405 Certificates of deposit and commercial paper — 911 — 911 Asset-backed securities — 231 — 231 Municipal debt securities — 115 — 115 Total available-for-sale investment securities 558 1,706 — 2,264 Held-to-maturity investment securities: Certificates of deposit and commercial paper — 40 — 40 Total held-to-maturity investment securities — 40 — 40 Total short-term investments (1) 558 2,552 — 3,110 Derivative financial instruments - foreign exchange forward contracts: Other current assets — 34 — 34 Accrued expenses and other current liabilities — (4 ) — (4 ) Other noncurrent assets — 17 — 17 Total $ 1,182 $ 2,730 $ — $ 3,912 ________________ (1) Excludes trading securities invested in a mutual fund valued at $25 million based on the NAV of the fund at December 31, 2016. We measure the fair value of money market funds and U.S. Treasury securities based on quoted prices in active markets for identical assets and therefore classify these assets as Level 1. The fair value of commercial paper, certificates of deposit, U.S. government agency securities, municipal debt securities, debt securities issued by supranational institutions, U.S. and international corporate bonds and foreign government debt securities is measured based on relevant trade data, dealer quotes, or model-driven valuations using significant inputs derived from or corroborated by observable market data, such as yield curves and credit spreads. We measure the fair value of our asset-backed securities using model-driven valuations based on significant inputs derived from or corroborated by observable market data such as dealer quotes, available trade information, spread data, current market assumptions on prepayment speeds and defaults and historical data on deal collateral performance. The carrying value of the time deposits approximated fair value as of December 31, 2017 and 2016 . We estimate the fair value of each foreign exchange forward contract by using a present value of expected cash flows model. This model calculates the difference between the current market forward price and the contracted forward price for each foreign exchange contract and applies the difference in the rates to each outstanding contract. The market forward rates include a discount and credit risk factor. The amounts are aggregated by type of contract and maturity. During the years ended December 31, 2017 , 2016 and 2015 , there were no transfers among Level 1, Level 2 or Level 3 financial assets and liabilities.

Stockholder's Equity

Stockholder's Equity	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity Stock Repurchase Program Effective March 1, 2017, the Board of Directors approved the termination of the stock repurchase program then in effect and approved a new stock repurchase program. The stock repurchase program allows for the repurchase of $3,500 million of our outstanding shares of Class A common stock, excluding fees and expenses, through December 31, 2019. In March 2017, we entered into accelerated stock repurchase agreements, referred to collectively as the March ASR, with certain financial institutions under our stock repurchase program. Under the terms of the ASR and in exchange for up-front payments of $1,500 million , the financial institutions delivered 23.7 million shares. The March ASR was completed in August 2017. The final number of shares repurchased was based on the final volume-weighted average price of the Company's Class A common stock during the purchase period less the negotiated discount. In December 2017, we entered into another accelerated stock repurchase agreement, or December ASR, with a financial institution under our stock repurchase program. Under the terms of the December ASR and in exchange for an up-front payment of $300 million , the financial institution initially delivered 3.6 million shares, a portion of the Company's total expected shares to be repurchased under the December ASR. The total number of shares ultimately delivered will be determined in the first quarter of 2018, at the end of the applicable purchase period. The combined March ASR and December ASR were accounted for as a $630 million reduction in common stock and additional paid-in capital and a $1,170 million reduction in retained earnings in our consolidated statements of financial position. As of December 31, 2017, the remaining available balance under our stock repurchase program was $1,700 million . The ASRs met all of the applicable criteria for equity classification, and therefore were not accounted for as derivative instruments. Additionally, stock repurchases were made in connection with our stock-based compensation plans, whereby Company shares were tendered by employees for payment of applicable statutory tax withholdings. In 2017, we also repurchased a limited number of shares from employees at the repurchase date market price. Combined such repurchases in 2017, 2016 and 2015 totaled 1.3 million , 1.2 million and 1.3 million shares, respectively, at an aggregate cost of $89 million , $72 million and $84 million , respectively. Dividends Dividends on our Class A common stock during the year were as follows: Dividends per Share Amount (in millions) Three months ended June 30, 2017 $ 0.15 $ 89 Three months ended September 30, 2017 0.15 90 Three months ended December 31, 2017 0.15 89 Year ended December 31, 2017 $ 268 We did not pay any dividends during 2016 or 2015. On February 5, 2018, our Board of Directors approved the Company's declaration of a $0.20 per share dividend with a record date of February 22, 2018 and a payment date of February 28, 2018. Accumulated Other Comprehensive Income (Loss) Changes in accumulated other comprehensive income (loss) by component were as follows for the year ended December 31, 2017 : 2017 Before Tax Amount Tax Effect Net of Tax Amount (in millions) Foreign currency translation adjustments: Beginning balance $ (149 ) $ — $ (149 ) Change in foreign currency translation adjustments 111 — 111 Ending balance $ (38 ) $ — $ (38 ) Unrealized (losses) on available-for-sale investment securities: Beginning balance $ (6 ) $ 2 $ (4 ) Net unrealized losses arising during the period (7 ) 3 (4 ) Reclassification of net losses to Other, net 2 (1 ) 1 Net change (5 ) 2 (3 ) Ending balance $ (11 ) $ 4 $ (7 ) Unrealized gains on cash flow hedges: Beginning balance $ 51 $ (12 ) $ 39 Unrealized gains arising during the period 232 (57 ) 175 Reclassifications of net (gains) to: Cost of revenues (109 ) 26 (83 ) Selling, general and administrative expenses (20 ) 4 (16 ) Net change 103 (27 ) 76 Ending balance $ 154 $ (39 ) $ 115 Accumulated other comprehensive income (loss): Beginning balance $ (104 ) $ (10 ) $ (114 ) Other comprehensive income (loss) 209 (25 ) 184 Ending balance $ 105 $ (35 ) $ 70 Changes in accumulated other comprehensive income (loss) by component were as follows for the years ended December 31, 2016 and 2015 : 2016 2015 Before Tax Amount Tax Effect Net of Tax Amount Before Tax Tax Net of Tax (in millions) Foreign currency translation adjustments: Beginning balance $ (90 ) $ — $ (90 ) $ (35 ) $ — $ (35 ) Change in foreign currency translation adjustments (59 ) — (59 ) (55 ) — (55 ) Ending balance $ (149 ) $ — $ (149 ) $ (90 ) $ — $ (90 ) Unrealized (losses) on available-for-sale investment securities: Beginning balance $ (7 ) $ 3 $ (4 ) $ (2 ) $ 1 $ (1 ) Net unrealized gains (losses) arising during the period 5 (2 ) 3 (4 ) 1 (3 ) Reclassification of net (gains) to Other, net (4 ) 1 (3 ) (1 ) 1 — Net change 1 (1 ) — (5 ) 2 (3 ) Ending balance $ (6 ) $ 2 $ (4 ) $ (7 ) $ 3 $ (4 ) Unrealized gains (losses) on cash flow hedges: Beginning balance $ (15 ) $ 3 $ (12 ) $ (103 ) $ 16 $ (87 ) Unrealized gains arising during the period 83 (19 ) 64 17 — 17 Reclassifications of net (gains) losses to: Cost of revenues (14 ) 3 (11 ) 59 (11 ) 48 Selling, general and administrative expenses (3 ) 1 (2 ) 12 (2 ) 10 Net change 66 (15 ) 51 88 (13 ) 75 Ending balance $ 51 $ (12 ) $ 39 $ (15 ) $ 3 $ (12 ) Accumulated other comprehensive income (loss): Beginning balance $ (112 ) $ 6 $ (106 ) $ (140 ) $ 17 $ (123 ) Other comprehensive income (loss) 8 (16 ) (8 ) 28 (11 ) 17 Ending balance $ (104 ) $ (10 ) $ (114 ) $ (112 ) $ 6 $ (106 )

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies We lease office space and equipment under operating leases, which expire at various dates through the year 2028. Certain leases contain renewal provisions and generally require us to pay utilities, insurance, taxes, and other operating expenses. Future minimum rental payments on our operating leases as of December 31, 2017 are as follows: Operating lease obligation (in millions) 2018 $ 188 2019 178 2020 156 2021 124 2022 87 Thereafter 210 Total minimum lease payments $ 943 Rental expense totaled $265 million, $227 million and $212 million for the years ended December 31, 2017 , 2016 and 2015 , respectively. Future minimum rental payments on our capital leases as of December 31, 2017 are as follows: Capital lease obligation (in millions) 2018 $ 9 2019 6 2020 5 2021 4 2022 4 Thereafter 23 Total minimum lease payments 51 Interest (10 ) Present value of minimum lease payments $ 41 We are involved in various claims and legal actions arising in the ordinary course of business. We accrue a liability when a loss is considered probable and the amount can be reasonably estimated. When a material loss contingency is reasonably possible but not probable, we do not record a liability, but instead disclose the nature and the amount of the claim, and an estimate of the loss or range of loss, if such an estimate can be made. Legal fees are expensed as incurred. In the opinion of management, the outcome of any existing claims and legal or regulatory proceedings, other than the specific matters described below, if decided adversely, is not expected to have a material adverse effect on our business, financial condition, results of operations and cash flows. We are conducting an internal investigation focused on whether certain payments relating to Company-owned facilities in India were made improperly and in possible violation of the FCPA and other applicable laws. The investigation is also examining various other payments made in small amounts in India that may not have complied with Company policy or applicable law. In September 2016, we voluntarily notified the DOJ and SEC and are cooperating fully with both agencies. The investigation is being conducted under the oversight of the Audit Committee, with the assistance of outside counsel. To date, the investigation has identified a total of approximately $6 million in payments made between 2009 and 2016 that may have been improper. During the year ended December 31, 2016, we recorded out-of-period corrections related to $4 million of such payments that were previously capitalized that should have been expensed. These out-of-period corrections and the other $2 million in potentially improper payments were not material to any previously issued financial statements. There were no adjustments recorded during the year ended December 31, 2017. On October 5, 2016, October 27, 2016, and November 18, 2016, three putative securities class action complaints were filed in the United States District Court for the District of New Jersey, naming us and certain of our current and former officers as defendants. In an order dated February 3, 2017, the United States District Court for the District of New Jersey consolidated the three putative securities class actions into a single action and appointed lead plaintiffs and lead counsel. On April 7, 2017, the lead plaintiffs filed a consolidated amended complaint on behalf of a putative class of stockholders who purchased our common stock during the period between February 27, 2015 and September 29, 2016, naming us and certain of our current and former officers as defendants and alleging violations of the Exchange Act, based on allegedly false or misleading statements related to potential violations of the FCPA, our business, prospects and operations, and the effectiveness of our internal controls over financial reporting and our disclosure controls and procedures. The lead plaintiffs seek an award of compensatory damages, among other relief, and their reasonable costs and expenses, including attorneys’ fees. Under a stipulation filed by the parties on February 23, 2017, defendants filed motions to dismiss the consolidated amended complaint on June 6, 2017, plaintiffs filed an opposition brief on July 21, 2017 responding to defendants’ motions to dismiss, and defendants filed reply briefs in further support of their motions to dismiss on September 5, 2017. On September 5, 2017, defendants also filed a motion to strike certain allegations in the consolidated amended complaint, plaintiffs filed an opposition to the motion to strike on October 2, 2017, and, on October 10, 2017, we filed a reply brief in further support of the motion to strike. On October 31, 2016, November 15, 2016, and November 18, 2016, three putative shareholder derivative complaints were filed in New Jersey Superior Court, Bergen County, naming us, all of our then current directors and certain of our current and former officers as defendants. On January 24, 2017, the New Jersey Superior Court, Bergen County, consolidated the three putative shareholder derivative actions filed in that court into a single action and appointed lead plaintiff and lead counsel. The complaints assert claims for breach of fiduciary duty, corporate waste, unjust enrichment, abuse of control, mismanagement, and/or insider selling by defendants. On March 16, 2017, the parties filed a stipulation deferring all further proceedings pending a final, non-appealable ruling on the then anticipated motion to dismiss the consolidated putative securities class action. On April 26, 2017, in lieu of ordering the stipulation filed by the parties, the New Jersey Superior Court deferred further proceedings by dismissing the consolidated putative shareholder derivative litigation without prejudice but permitting the parties to file a motion to vacate the dismissal in the future. On February 22, 2017, a fourth putative shareholder derivative complaint asserting similar claims was filed in the United States District Court for the District of New Jersey, naming us and certain of our then current directors as defendants. On April 5, 2017, the United States District Court for the District of New Jersey entered an order staying all proceedings pending a final, non-appealable ruling on the then anticipated motion to dismiss the consolidated putative securities class action. On April 7, 2017, a fifth putative shareholder derivative complaint was filed in the United States District Court for the District of New Jersey, naming us, certain of our then current directors, and certain of our current and former officers as defendants. The complaint in that action asserts claims similar to those in the previously-filed putative shareholder derivative actions, but also adds a claim for violations of Section 10(b) of the Exchange Act against the individual defendants. On May 10, 2017, a sixth putative shareholder derivative complaint was filed in the United States District Court for the District of New Jersey, naming us, certain of our then current directors, and certain of our current and former officers as defendants. The complaint in that action asserts claims similar to those in the previously-filed putative shareholder derivative actions, but also adds a claim for violations of Section 14(a) of the Exchange Act against the individual defendants. In an order dated June 20, 2017, the United States District Court for the District of New Jersey consolidated the three putative shareholder derivative actions filed in that court into a single action, appointed lead plaintiff and lead counsel, and stayed all further proceedings pending a final, non-appealable ruling on the motions to dismiss the consolidated putative securities class action. All of the putative shareholder derivative complaints allege among other things that certain of our public disclosures were false and misleading by failing to disclose that payments allegedly in violation of the FCPA had been made and by asserting that management had determined that our internal controls were effective. The plaintiffs seek awards of compensatory damages and restitution to the Company as a result of the alleged violations and their costs and attorneys’ fees, experts’ fees, and other litigation expenses, among other relief. We are presently unable to predict the duration, scope or result of the internal investigation, any investigations by the DOJ or the SEC, the consolidated putative securities class action, the putative shareholder derivative actions or any other lawsuits. As such, we are presently unable to develop a reasonable estimate of a possible loss or range of losses, if any, and thus have not recorded any accruals related to these matters. The DOJ and the SEC have a broad range of civil and criminal sanctions under the FCPA and other laws and regulations including injunctive relief, disgorgement, fines, penalties, modifications to business practices, including the termination or modification of existing business relationships, the imposition of compliance programs and the retention of a monitor to oversee compliance with the FCPA. In addition, the DOJ and the SEC could bring enforcement actions against the Company or individuals, including former members of senior management. Such actions, if brought, could result in dispositions, judgments, settlements, fines, injunctions, cease and desist orders, debarment or other civil or criminal penalties against the Company or such individuals. We expect to incur additional expenses related to remedial measures, and may incur additional expenses related to fines. The imposition of any sanctions or the implementation of remedial measures could have a material adverse effect on our business, annual and interim results of operations, cash flows and financial condition. Furthermore, while the Company intends to defend the lawsuits vigorously, these lawsuits and any other related lawsuits are subject to inherent uncertainties, the actual cost of such litigation will depend upon many unknown factors and the outcome of the litigation is necessarily uncertain. We have indemnification and expense advancement obligations pursuant to our Bylaws and indemnification agreements with respect to certain current and former members of senior management and the Company’s directors. In connection with the ongoing internal investigation, we have received requests under such indemnification agreements and our Bylaws to provide funds for legal fees and other expenses, and expect additional requests in connection with the investigation and related litigation. We have not recorded any liability for these matters as of December 31, 2017 as we cannot estimate the ultimate outcome at this time but have expensed payments made through December 31, 2017. We have maintained directors and officers insurance, from which a portion of the indemnification expenses and costs related to the putative securities class action complaints may be recoverable, and have recorded an insurance receivable of less than $1 million as of December 31, 2017. We are unable to make a reliable estimate of the eventual cash flows by period related to the indemnification agreements described here. Many of our engagements involve projects that are critical to the operations of our customers’ business and provide benefits that are difficult to quantify. Any failure in a customer’s systems or our failure to meet our contractual obligations to our customers, including any breach involving a customer’s confidential information or sensitive data, or our obligations under applicable laws or regulations could result in a claim for substantial damages against us, regardless of our responsibility for such failure. Although we attempt to contractually limit our liability for damages arising from negligent acts, errors, mistakes, or omissions in rendering our services, there can be no assurance that the limitations of liability set forth in our contracts will be enforceable in all instances or will otherwise protect us from liability for damages. Although we have general liability insurance coverage, including coverage for errors or omissions, there can be no assurance that such coverage will cover all types of claims, continue to be available on reasonable terms or will be available in sufficient amounts to cover one or more large claims, or that the insurer will not disclaim coverage as to any future claim. The successful assertion of one or more large claims against us that exceed or are not covered by our insurance coverage or changes in our insurance policies, including premium increases or the imposition of large deductible or co-insurance requirements, could have a material adverse effect on our business, results of operations, financial condition and cash flows. In the normal course of business and in conjunction with certain customer engagements, we have entered into contractual arrangements through which we may be obligated to indemnify customers or other parties with whom we conduct business with respect to certain matters. These arrangements can include provisions whereby we agree to hold the indemnified party and certain of their affiliated entities harmless with respect to third-party claims related to such matters as our breach of certain representations or covenants, our intellectual property infringement, our gross negligence or willful misconduct or certain other claims made against certain parties. Payments by us under any of these arrangements are generally conditioned on the customer making a claim and providing us with full control over the defense and settlement of such claim. It is not possible to determine the maximum potential liability under these indemnification agreements due to the unique facts and circumstances involved in each particular agreement. Historically, we have not made payments under these indemnification agreements and therefore they have not had any impact on our operating results, financial position, or cash flows. However, if events arise requiring us to make payment for indemnification claims under our indemnification obligations in contracts we have entered, such payments could have material impact on our business, results of operations, financial condition and cash flows.

Employee Benefits

Employee Benefits	12 Months Ended
	Dec. 31, 2017
Retirement Benefits, Description [Abstract]
Employee Benefits	Employee Benefits We contribute to defined contribution plans in the United States and Europe, including 401(k) savings and supplemental retirement plans in the United States. Total expenses for our contributions to these plans were $91 million, $76 million and $62 million for the years ended December 31, 2017 , 2016 and 2015 , respectively. We maintain employee benefit plans that cover substantially all India-based employees. The employees’ provident fund, pension and family pension plans are statutorily defined contribution retirement benefit plans. Under the plans, employees contribute up to 12.0% of their base compensation, which is matched by an equal contribution by the Company. For these plans, we recognized a contribution expense of $86 million, $79 million and $71 million for the years ended December 31, 2017 , 2016 and 2015 , respectively. We also maintain a gratuity plan in India that is a statutory post-employment benefit plan providing defined lump sum benefits. We make annual contributions to the employees’ gratuity fund established with a government-owned insurance corporation to fund a portion of the estimated obligation. Accordingly, our liability for the gratuity plan reflects the undiscounted benefit obligation payable as of the balance sheet date which was based upon the employees’ salary and years of service. As of December 31, 2017 and 2016 , the amount accrued under the gratuity plan was $114 million and $106 million, which is net of fund assets of $138 million and $103 million, respectively. Expense recognized by us was $40 million, $41 million and $30 million for the years ended December 31, 2017 , 2016 and 2015 , respectively.

Stock-Based Compensation Plans

Stock-Based Compensation Plans	12 Months Ended
	Dec. 31, 2017
Share-based Compensation [Abstract]
Stock-Based Compensation Plans	Stock-Based Compensation Plans The Company's 2017 Incentive Award Plan, or the 2017 Incentive Plan, and the 2004 Employee Stock Purchase Plan, or the Purchase Plan, as amended in 2013, provide for the issuance of up to 48.8 million (plus any shares underlying outstanding awards that are forfeited under the Company’s Amended and Restated 2009 Incentive Compensation Plan, or 2009 Incentive Plan) and 28.0 million shares, respectively, of Class A common stock to eligible employees. The 2017 Incentive Plan does not affect any awards outstanding under the 2009 Incentive Plan. As of December 31, 2017 , we have 46.1 million and 2.4 million shares available for grant under the 2017 Incentive Plan and the Purchase Plan, respectively. Stock options granted to employees under our plans have a life ranging from seven to ten years , vest proportionally over four years , unless specified otherwise, and have an exercise price equal to the fair market value of the common stock on the date of grant. Grants to non-employee directors vest proportionally over two years . Stock-based compensation expense relating to stock options is recognized on a straight-line basis over the requisite service period. Restricted stock units, or RSUs, vest proportionately in quarterly or annual installments over one to four years . Stock-based compensation expense relating to RSUs is recognized on a straight-line basis over the requisite service period. We granted performance stock units, or PSUs, that vest over periods ranging from one to three years to employees, including our executive officers. The vesting of PSUs is contingent on both meeting certain financial performance targets and continued service. Stock-based compensation costs for PSUs that vest proportionally are recognized on a graded-vesting basis over the vesting period based on the most probable outcome of the performance conditions. If the minimum performance targets are not met, no compensation cost is recognized and any recognized compensation cost is reversed. All RSUs and PSUs have dividend equivalent rights, which entitle holders to the same dividend value per share as holders of common stock. Dividend equivalent rights are subject to the same vesting and other terms and conditions as the corresponding unvested RSUs and PSUs and are accumulated and paid when the underlying shares vest. The Purchase Plan provides for eligible employees to purchase shares of Class A common stock at a price of 90% of the lesser of: (a) the fair market value of a share of Class A common stock on the first date of the purchase period or (b) the fair market value of a share of Class A common stock on the last date of the purchase period. Stock-based compensation expense for the Purchase Plan is recognized over the vesting period of three months on a straight-line basis. The allocation of total stock-based compensation expense between cost of revenues and selling, general and administrative expenses as well as the related income tax benefit were as follows for the three years ended December 31: 2017 2016 2015 (in millions) Cost of revenues $ 55 $ 53 $ 39 Selling, general and administrative expenses 166 164 153 Total stock-based compensation expense $ 221 $ 217 $ 192 Income tax benefit $ 101 $ 49 $ 46 In 2017, as a result of the adoption of new authoritative stock compensation guidance, we recognized net excess tax benefits upon exercise or vesting of stock-based compensation awards in our income tax provision in the amount of $40 million or $0.07 per share. In 2016 and 2015, such excess tax benefits were recorded in additional paid in capital. We estimate the fair value of each stock option granted using the Black-Scholes option-pricing model. For the years ended December 31, 2017 , 2016 and 2015 , expected volatility was calculated using implied market volatilities. In addition, the expected term, which represents the period of time, measured from the grant date, that vested options are expected to be outstanding, was derived by incorporating exercise and post-vest termination assumptions, based on historical data, in a Monte Carlo simulation model. The risk-free rate is derived from the U.S. Treasury yield curve in effect at the time of grant. The expected dividend yield is based on the annual dividend amount expected on the date of grant divided by the stock price on the date of grant. Forfeiture assumptions used to recognize stock-based compensation expense are based on an analysis of historical data. The fair values of option grants, including the Purchase Plan, were estimated at the date of grant during the years ended December 31, 2017 , 2016 , and 2015 based upon the following assumptions and were as follows: 2017 2016 2015 Dividend yield 1.0 % 0.0 % 0.0 % Weighted average volatility factor: Stock options 25.9 % 28.3 % 28.1 % Purchase Plan 24.3 % 26.5 % 25.8 % Weighted average expected life (in years): Stock options 4.36 4.46 4.29 Purchase Plan 0.25 0.25 0.25 Weighted average risk-free interest rate: Stock options 1.9 % 1.1 % 1.4 % Purchase Plan 0.9 % 0.4 % 0.1 % Weighted average grant date fair value: Stock options $ 13.06 $ 15.17 $ 16.53 Purchase Plan $ 9.23 $ 8.74 $ 9.04 During the year ended December 31, 2017 , we issued 2.8 million shares of Class A common stock under the Purchase Plan with a total vested fair value of approximately $26 million. A summary of the activity for stock options granted under our stock-based compensation plans as of December 31, 2017 and changes during the year then ended is presented below: Number of Options (in millions) Weighted Average Exercise Price (in dollars) Weighted Average Remaining Life (in years) Aggregate Intrinsic Value (in millions) Outstanding at January 1, 2017 2.4 $ 21.08 Granted — — Exercised (1.7 ) 19.76 Cancelled — — Expired — — Outstanding at December 31, 2017 0.7 $ 24.88 1.6 $ 29 Vested and expected to vest at December 31, 2017 0.7 $ 24.78 1.6 $ 29 Exercisable at December 31, 2017 0.7 $ 23.28 1.5 $ 29 As of December 31, 2017 , $0.2 million of total remaining unrecognized stock-based compensation cost related to stock options is expected to be recognized over the weighted-average remaining requisite service period of 0.5 years . The total intrinsic value of options exercised was $78 million, $74 million and $59 million for the years ended December 31, 2017 , 2016 and 2015 , respectively. The fair value of RSUs and PSUs is determined based on the number of stock units granted and the quoted price of our stock at date of grant. A summary of the activity for PSUs granted under our stock-based compensation plans as of December 31, 2017 and changes during the year then ended is presented below. The presentation reflects the number of PSUs at the maximum performance milestones. Number of Units (in millions) Weighted Average Grant Date Fair Value (in dollars) Unvested at January 1, 2017 2.7 $ 55.24 Granted 2.0 60.77 Vested (0.9 ) 55.07 Forfeited (0.4 ) 56.81 Reduction due to the achievement of lower than maximum performance milestones (0.7 ) 55.04 Unvested at December 31, 2017 2.7 $ 59.15 As of December 31, 2017 , $60 million of total remaining unrecognized stock-based compensation cost related to PSUs is expected to be recognized over the weighted-average remaining requisite service period of 1.2 years. A summary of the activity for RSUs granted under our stock-based compensation plans as of December 31, 2017 and changes during the year then ended is presented below: Number of Units (in millions) Weighted Average Grant Date Fair Value (in dollars) Unvested at January 1, 2017 4.8 $ 56.45 Granted 3.6 67.56 Vested (2.5 ) 56.81 Forfeited (0.7 ) 57.63 Unvested at December 31, 2017 5.2 $ 63.80 As of December 31, 2017 , $282 million of total remaining unrecognized stock-based compensation cost related to RSUs is expected to be recognized over the weighted-average remaining requisite service period of 2.2 years.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2017
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Brackett B. Denniston, III was the Interim General Counsel and an executive officer of the Company from December 2016 until May 15, 2017. Mr. Denniston is, and was during such period, a Senior Counsel at the law firm of Goodwin Procter LLP, or Goodwin. During the years ended December 31, 2017 and 2016, Goodwin performed legal services for the Company for which it earned approximately $4 million and $ 2 million, respectively. Goodwin has continued to perform such legal services since December 31, 2017 through the date of this filing. Goodwin did not perform any services for the Company during the year ended December 31, 2015. The provision of legal services by Goodwin was reviewed and approved by our Audit Committee.

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2017
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Segment Information	Segment Information Our reportable segments are: • Financial Services, which consists of our banking and insurance operating segments; • Healthcare, which consists of our healthcare and life sciences operating segments; • Products and Resources (previously referred to as Manufacturing/Retail/Logistics), which consists of our retail and consumer goods, manufacturing and logistics, travel and hospitality, and energy and utilities operating segments; and • Communications, Media and Technology (previously referred to as Other), which includes our communications and media operating segment and our technology operating segment. Our sales managers, account executives, account managers and project teams are aligned in accordance with the specific industries they serve. Our chief operating decision maker evaluates the Company’s performance and allocates resources based on segment revenues and operating profit. Segment operating profit is defined as income from operations before unallocated costs. Generally, operating expenses for each operating segment have similar characteristics and are subject to the same factors, pressures and challenges. However, the economic environment and its effects on industries served by our operating segments may affect revenues and operating expenses to differing degrees. Expenses included in segment operating profit consist principally of direct selling and delivery costs as well as a per seat charge for use of the global delivery centers. Certain selling, general and administrative expenses, excess or shortfall of incentive compensation for delivery personnel as compared to target, stock-based compensation expense, a portion of depreciation and amortization, costs related to our realigment program and the impact of the settlements of our cash flow hedges are not allocated to individual segments in internal management reports used by the chief operating decision maker. Accordingly, such expenses are excluded from segment operating profit and are separately disclosed as “unallocated costs” and adjusted only against our total income from operations. Additionally, management has determined that it is not practical to allocate identifiable assets by segment, since such assets are used interchangeably among the segments. Revenues from external customers and segment operating profit, before unallocated costs, by reportable segment were as follows: 2017 2016 2015 (in millions) Revenues: Financial Services $ 5,636 $ 5,366 $ 5,003 Healthcare 4,263 3,871 3,668 Products and Resources 3,040 2,660 2,344 Communications, Media and Technology 1,871 1,590 1,401 Total revenues $ 14,810 $ 13,487 $ 12,416 Segment Operating Profit: Financial Services $ 1,636 $ 1,707 $ 1,642 Healthcare 1,304 1,153 1,200 Products and Resources 868 851 803 Communications, Media and Technology 565 488 453 Total segment operating profit 4,373 4,199 4,098 Less: unallocated costs 1,892 1,910 1,956 Income from operations $ 2,481 $ 2,289 $ 2,142 Geographic Area Information Revenues and long-lived assets, by geographic area, were as follows: 2017 2016 2015 (in millions) Revenues: (1) North America (2) $ 11,450 $ 10,546 $ 9,759 United Kingdom 1,150 1,176 1,188 Rest of Europe 1,248 969 820 Europe - Total 2,398 2,145 2,008 Rest of World (3) 962 796 649 Total $ 14,810 $ 13,487 $ 12,416 2017 2016 2015 (in millions) Long-lived Assets: (4) North America (2) $ 360 $ 279 $ 242 Europe 63 52 32 Rest of World (3)(5) 901 980 997 Total $ 1,324 $ 1,311 $ 1,271 _____________ (1) Revenues are attributed to regions based upon customer location. (2) Substantially all relates to operations in the United States. (3) Includes our operations in Asia Pacific, the Middle East and Latin America. (4) Long-lived assets include property and equipment, net of accumulated depreciation and amortization. (5) Substantially all of these long-lived assets relate to our operations in India.

Quarterly Financial Data (Unaud

Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Data [Abstract]
Quarterly Financial Data (Unaudited)	Quarterly Financial Data (Unaudited) Summarized quarterly results for the two years ended December 31, 2017 are as follows: Three Months Ended 2017 March 31 June 30 September 30 December 31 Full Year (in millions, except per share data) Revenues $ 3,546 $ 3,670 $ 3,766 $ 3,828 $ 14,810 Cost of revenues (exclusive of depreciation and amortization expense shown separately below) 2,194 2,261 2,337 2,360 9,152 Selling, general and administrative expenses 686 709 674 700 2,769 Depreciation and amortization expense 96 94 107 111 408 Income from operations 570 606 648 657 2,481 Net income (loss) (1) 557 470 495 (18 ) 1,504 Basic earnings (losses) per share (2) (3) $ 0.92 $ 0.80 $ 0.84 $ (0.03 ) $ 2.54 Diluted earnings (losses) per share (2) (3) $ 0.92 $ 0.80 $ 0.84 $ (0.03 ) $ 2.53 Three Months Ended 2016 March 31 June 30 September 30 December 31 Full Year (in millions, except per share data) Revenues $ 3,202 $ 3,370 $ 3,453 $ 3,462 $ 13,487 Cost of revenues (exclusive of depreciation and amortization expense shown separately below) 1,915 2,038 2,077 2,078 8,108 Selling, general and administrative expenses 646 654 701 730 2,731 Depreciation and amortization expense 87 87 92 93 359 Income from operations 554 591 583 561 2,289 Net income 441 252 444 416 1,553 Basic earnings per share (2) $ 0.73 $ 0.42 $ 0.73 $ 0.69 $ 2.56 Diluted earnings per share (2) $ 0.72 $ 0.41 $ 0.73 $ 0.68 $ 2.55 ____________________________ (1) The net loss for the quarter ended December 31, 2017, includes the one-time provisional incremental income tax expense relating to the Tax Reform Act. See Note 10 to our consolidated financial statements. (2) The sum of the quarterly basic and diluted earnings (losses) per share for each of the four quarters may not equal the earnings (losses) per share for the year due to rounding. (3) In March 2016, the FASB issued an update related to stock compensation. The update simplified the accounting for excess tax benefits and deficiencies related to employee stock-based payment transactions. We adopted this standard prospectively on January 1, 2017. For the first, second, third and fourth quarters of 2017, we recognized net excess tax benefits on stock-based compensation awards in our income tax provision in the amount of $6 million , $5 million , $5 million and $24 million , respectively. This impacted our earnings per shares in the first, second, third and fourth quarters of 2017 by $0.01 , $0.01 , $0.01 and $0.04 per share, respectively. In prior periods, such net excess tax benefits were recorded in additional paid in capital.

Valuation And Qualifying Accoun

Valuation And Qualifying Accounts	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
Valuation And Qualifying Accounts	Valuation and Qualifying Accounts For the Years Ended December 31, 2017 , 2016 and 2015 (in millions) Description Balance at Beginning of Period Charged to Costs and Expenses Charged to Other Accounts Deductions /Other Balance at End of Period (in millions) Trade accounts receivable allowance for doubtful accounts: 2017 $ 48 $ 15 $ 3 $ 1 $ 65 2016 $ 39 $ 12 $ — $ 3 $ 48 2015 $ 37 $ 10 $ — $ 8 $ 39 Warranty accrual: 2017 $ 26 $ 30 $ — $ 26 $ 30 2016 $ 24 $ 28 $ — $ 26 $ 26 2015 $ 21 $ 28 $ — $ 25 $ 24 Valuation allowance—deferred income tax assets: 2017 $ 10 $ — $ — $ — $ 10 2016 $ 10 $ — $ — $ — $ 10 2015 $ 11 $ 3 $ — $ 4 $ 10

Business Description and Summ28

Business Description and Summary of Significant Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Basis of Presentation And Principles of Consolidation	Basis of Presentation, Principles of Consolidation and Use of Estimates. The consolidated financial statements are presented in accordance with generally accepted accounting principles in the United States of America, or GAAP, and reflect the consolidated financial position, results of operations, comprehensive income and cash flows of our consolidated subsidiaries for all periods presented. All intercompany balances and transactions have been eliminated in consolidation.
Cash And Cash Equivalents And Investments	Cash and Cash Equivalents and Investments. Cash and cash equivalents consist of all cash balances, including money market funds and liquid instruments. Liquid instruments are classified as cash equivalents when their maturities at the date of purchase are 90 days or less and as short-term investments when their maturities at the date of purchase are greater than 90 days. We determine the appropriate classification of our investments in marketable securities at the date of purchase and reevaluate such designation at each balance sheet date. We have classified and accounted for our marketable securities as either trading, available-for-sale or held-to-maturity. After consideration of our risk versus reward objectives, as well as our liquidity requirements, we may sell our trading and available-for-sale securities prior to their stated maturities. We classify these marketable securities with maturities at the date of purchase beyond 90 days as short-term investments based on their highly liquid nature and because such marketable securities represent an investment of cash that is available for current operations. Our held-to-maturity investment securities are financial instruments for which we have the intent and ability to hold to maturity and we classify these securities with maturities beyond 90 days but less than one year as short-term investments. Any held-to-maturity investment securities with maturities beyond one year from the balance sheet date are classified as noncurrent. Trading securities are reported at fair value with changes in unrealized gains and losses recorded in Other income (expense), net in our consolidated statements of operations. Available-for-sale securities are reported at fair value with changes in unrealized gains and losses recorded as a separate component of accumulated other comprehensive income (loss) until realized. We determine the cost of the securities sold based on the specific identification method. Held-to-maturity securities are reported at amortized cost. Time deposits with financial institutions are valued at cost, which approximates fair value. Interest and amortization of premiums and discounts for debt securities are included in interest income. On a quarterly basis, we evaluate our available-for-sale and held-to-maturity investments for possible other-than-temporary impairment by reviewing quantitative and qualitative factors.
Allowance For Doubtful Accounts	Allowance for Doubtful Accounts. We maintain an allowance for doubtful accounts for estimated losses resulting from the inability of our customers to make required payments. The allowance for doubtful accounts is determined by evaluating the relative credit-worthiness of each customer, historical collections experience and other information, including the aging of the receivables. We evaluate the collectibility of our accounts receivable on an on-going basis and write off accounts when they are deemed to be uncollectible.
Unbilled Accounts Receivable	Unbilled Accounts Receivable. Unbilled accounts receivable represent revenues recognized that are to be billed in subsequent periods, as per the terms of the related contracts.
Short-Term Financial Assets And Liabilities	Short-term Financial Assets and Liabilities. Cash and certain cash equivalents, trade receivables, accounts payable and other accrued liabilities are short-term in nature and, accordingly, their carrying values approximate fair value.
Property And Equipment	Property and Equipment. Property and equipment are stated at cost, net of accumulated depreciation. Depreciation is calculated on a straight-line basis over the estimated useful lives of the assets. Leasehold improvements are amortized on a straight-line basis over the shorter of the term of the lease or the estimated useful life of the improvement. In India, leasehold land is leased by us from the government of India with lease terms ranging up to 99 years. Lease payments are made at the inception of the lease agreement and amortized over the lease term. Maintenance and repairs are expensed as incurred, while renewals and betterments are capitalized. Deposits paid towards acquisition of long-lived assets and the cost of assets not put in use before the balance sheet date are disclosed under the caption “Capital work-in-progress” in Note 6 .
Internal Use Software	Internal Use Software. We capitalize certain costs that are incurred to purchase, develop and implement internal-use software during the application development phase, which primarily include coding, testing and certain data conversion activities. Capitalized costs are amortized on a straight-line basis over the useful life of the software. Costs incurred in performing activities associated with the preliminary project phase and the post-implementation phase are expensed as incurred.
Software to be Sold Leased or Marketed	Software to be Sold, Leased or Marketed. We capitalize costs incurred after technological feasibility is reached but before software is available for general release to customers, which primarily include coding and testing activities. Once the product is ready for general release, capitalized costs are amortized over the useful life of the software.
Business Combinations	Business Combinations. We account for business combinations using the acquisition method, which requires the identification of the acquirer, the determination of the acquisition date and the allocation of the purchase price paid by the acquirer to the identifiable tangible and intangible assets acquired, the liabilities assumed, including any contingent consideration and any noncontrolling interest in the acquiree at their acquisition date fair values. Goodwill represents the excess of the purchase price over the fair value of net assets acquired, including the amount assigned to identifiable intangible assets. Identifiable intangible assets with finite lives are amortized over their useful lives. Acquisition-related costs are expensed in the periods in which the costs are incurred. The results of operations of acquired businesses are included in our consolidated financial statements from the acquisition date .
Equity Method Investments And Cost Method Investments	Equity Method Investments. Equity investments that give us the ability to exercise significant influence, but not control, over an investee are accounted for using the equity method of accounting and recorded in the caption "Long-term investments" on our consolidated statements of financial position. Equity method investments are initially recorded at cost and any excess cost over our proportionate share of the fair value of the net assets of the investee at the acquisition date is recognized as goodwill and included in the carrying amount of the investment. We periodically review the carrying value of our equity method investments to determine if there has been an other-than-temporary decline in carrying value. The Company's proportionate share of the net income or loss of the investee is recorded in the caption "Income from equity method investments" on our consolidated statements of operations. The investment balance is increased or decreased for cash contributions or distributions to or from these investees. If we subsequently obtain control of the investee, the existing carrying value of the investment is remeasured to the fair value on the change of control date and any gain or loss is recognized in results of operations. Cost Method Investments. Equity investments without readily determinable fair values in which we do not exercise significant influence or control are accounted for using the cost method of accounting and recorded in the caption "Long-term investments" on our consolidated statements of financial position. Investments are carried at cost and are adjusted only for other-than-temporary declines in fair value, certain distributions and additional investments. We periodically review the carrying value of our cost method investments to determine if there has been an other-than-temporary decline in carrying value.
Long-Lived Assets And Finite-Lived Intangibles	Long-lived Assets and Finite-lived Intangibles. We review long-lived assets and certain finite-lived identifiable intangibles for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. We recognize an impairment loss when the sum of undiscounted expected future cash flows is less than the carrying amount of such assets. The impairment loss is determined as the amount by which the carrying amount of the asset exceeds the fair value of the asset. Intangible assets consist primarily of customer relationships and developed technology, which are being amortized on a straight-line basis over their estimated useful lives.
Goodwill And Indefinite-Lived intangibles	Goodwill and Indefinite-lived Intangibles. We evaluate goodwill and indefinite-lived intangible assets for impairment at least annually, or as circumstances warrant. Goodwill is evaluated at the reporting unit level by comparing the fair value of the reporting unit with its carrying amount including goodwill. An impairment of goodwill exists if the carrying amount of the reporting unit exceeds its fair value. The impairment loss is the amount by which the carrying amount exceeds the reporting unit’s fair value, limited to the total amount of goodwill allocated to that reporting unit. For indefinite-lived intangible assets, if our annual qualitative assessment indicates that it is more-likely-than-not that an indefinite-lived intangible asset is impaired, we test the assets for impairment by comparing the fair value of such assets to their carrying value. If an impairment is indicated, a write down to the fair value of indefinite-lived intangible asset is recorded.
Stock Repurchase Program	Stock Repurchase Program. Under the Board of Directors authorized stock repurchase program, the Company is authorized to repurchase its Class A common stock through open market purchases, including under a trading plan adopted pursuant to Rule 10b5-1 of the Exchange Act, or in private transactions, including through accelerated stock repurchase agreements (or ASRs) entered into with financial institutions, in accordance with applicable federal securities laws. We account for the repurchased shares as constructively retired. Shares are returned to the status of authorized and unissued shares at the time of repurchase or in the periods they are delivered, if repurchased under an ASR. To reflect share repurchases in the consolidated statement of financial position, the Company (i) reduces common stock for the par value of the shares, (ii) reduces additional paid-in capital for the amount in excess of par during the period in which the shares are repurchased and (iii) records any residual amount in excess of available additional paid-in capital to retained earnings. Upfront payments related to ASRs are accounted for as a reduction to stockholders’ equity in the consolidated statement of financial position in the period the payments are made.
Revenue Recognition	Revenue Recognition. Revenues related to time-and-materials contracts are recognized as the service is performed and amounts are earned. Revenues from transaction- or volume-based priced contracts are recognized as transactions are processed and amounts are earned. Revenues related to fixed-price contracts for highly complex application development and systems integration services are recognized as the service is performed using the percentage of completion method of accounting, under which the total value of revenues is recognized on the basis of the percentage that each contract’s total labor cost to date bears to the total expected labor costs (cost to cost method). Revenues related to fixed-price outsourcing services are recognized on a straight-line basis unless revenues are earned and obligations are fulfilled in a different pattern. Revenues related to fixed-price contracts for consulting or other technology services are recognized as services are performed on a proportional performance basis based upon the level of effort. For all services, revenues are earned and recognized only when all of the following criteria are met: evidence of an arrangement exists, the price is fixed or determinable, the services have been rendered and collectibility is reasonably assured. Contingent or incentive revenues are recognized when the contingency is satisfied and we conclude the amounts are earned. Volume discounts are recorded as a reduction of revenues as services are provided. Revenues also include the reimbursement of out-of-pocket expenses. Costs to deliver services are expensed as incurred with the exception of specific costs directly related to transition or set-up activities for outsourcing contracts. Transition costs are deferred and expensed ratably over the period of service. Deferred amounts are protected by collected cash or early termination penalty clauses and are monitored regularly for impairment. Impairment losses are recorded when projected remaining undiscounted operating cash flows of the related contract are not sufficient to recover the carrying amount of the contract assets. Deferred transition costs were approximately $ 267 million and $ 188 million as of December 31, 2017 and 2016 , respectively, and are included in other noncurrent assets in our consolidated statements of financial position. Costs related to warranty provisions are accrued at the time the related revenues are recorded. We may enter into arrangements that consist of multiple elements. Such arrangements may include any combination of our products, solutions and services. For arrangements with multiple deliverables, we evaluate at the inception of each new arrangement all deliverables to determine whether they represent separate units of accounting. For arrangements with multiple units of accounting, other than arrangements that contain software licenses and software-related services, we allocate consideration among the units of accounting, where separable, based on their relative selling price. Relative selling price is determined based on vendor-specific objective evidence, or VSOE, if it exists. Otherwise, third-party evidence of selling price is used, when it is available, and in circumstances when neither VSOE nor third-party evidence of selling price is available, management’s best estimate of selling price is used. Revenues are recognized for each unit of accounting based on our revenue recognition policy described above. Fixed-price contracts are generally cancelable subject to a specified notice period. All services provided by us through the date of cancellation are due and payable under the contract terms. We issue invoices related to fixed-price contracts based upon achievement of milestones during a project or other contractual terms. Differences between the timing of billing, based on contract milestones or other contractual terms, and the recognition of revenues are recognized as either unbilled receivables or deferred revenue. Estimates of certain fixed-price contracts are subject to adjustment as a project progresses to reflect changes in expected completion costs or efforts. The cumulative impact of any revision in estimates is reflected in the financial reporting period in which the change in estimate becomes known and any anticipated losses on contracts are recognized immediately. We also generate product revenues from licensing our software. For perpetual software license arrangements that do not require significant modification or customization of the underlying software, revenues are recognized when the software is delivered and all other software revenue recognition criteria are met. For software license arrangements that require significant functionality enhancements or modification of the software, revenues for the software license and those services are recognized as those services are performed. For software license arrangements that include a right to use the product for a defined period of time, we recognize revenues ratably over the term of the license. We may enter into arrangements with customers that purchase both software licenses and software-related services from us at the same time, or within close proximity of one another (referred to as software-related multiple-element arrangements). Such software related multiple-element arrangements may include software licenses, software license updates, product support contracts and other software-related services. For those software related multiple-element arrangements, we apply the residual method to determine the amount of software license revenues. Under the residual method, if VSOE of fair value exists for undelivered elements in a multiple-element arrangement, revenues equal to the fair value of the undelivered elements are deferred with the remaining portion of the arrangement consideration generally recognized upon delivery of the software license. For arrangements in which VSOE of fair value does not exist for each software-related undelivered element, revenues for the software license are deferred and not recognized until VSOE of fair value is available for the undelivered element or delivery of each element has occurred. If the only undelivered element is a service, revenues from the delivered element are recognized over the service period. We also enter into multiple-element arrangements that may include a combination of software licenses and various software-related and non-software-related services. In such arrangements, we first allocate the total arrangement consideration, based on relative selling prices, between the software group of elements and the non-software group of elements. We then further allocate consideration within the software group to the respective elements within that group following the software-related multiple-element arrangements policies described above. For the non-software group of elements, we further allocate consideration to the respective elements based on relative selling prices. After the arrangement consideration has been allocated to the individual elements, we account for each respective element in the arrangement as described above.
Stock-Based Compensation	Stock-Based Compensation. Stock-based compensation expense for awards of equity instruments to employees and non-employee directors is determined based on the grant-date fair value of those awards. We recognize these compensation costs net of an estimated forfeiture rate over the requisite service period of the award. Forfeitures are estimated on the date of grant and revised if actual or expected forfeiture activity differs materially from original estimates.
Foreign Currency	Foreign Currency. The assets and liabilities of our foreign subsidiaries whose functional currency is not the U.S. dollar are translated into U.S. dollars from functional currencies at current exchange rates while revenues and expenses are translated from functional currencies at average monthly exchange rates. The resulting translation adjustments are recorded in the caption "Accumulated other comprehensive income (loss)" on the accompanying consolidated statements of financial position. Foreign currency transactions and balances are those that are denominated in a currency other than the subsidiary’s functional currency. The U.S. dollar is the functional currency for certain foreign subsidiaries who conduct business predominantly in U.S. dollars. For these subsidiaries, transactions and balances denominated in the local currency are foreign currency transactions. Foreign currency transactions and balances related to non-monetary assets and liabilities are remeasured to the functional currency of the subsidiary at historical exchange rates while monetary assets and liabilities are remeasured to the functional currency of the subsidiary at current exchange rates. Foreign currency exchange gains or losses from remeasurement are included in the caption "Foreign currency exchange gain (losses), net" on our consolidated statement of operations together with gains or losses on our undesignated foreign currency hedges.
Derivative Financial Instruments	Derivative Financial Instruments. Derivative financial instruments are recorded on the balance sheet as either an asset or liability measured at its fair value as of the reporting date. Our derivative financial instruments consist of foreign exchange forward contracts. For derivative financial instruments to qualify for hedge accounting, the following criteria must be met: (1) the hedging instrument must be designated as a hedge; (2) the hedged exposure must be specifically identifiable and must expose us to risk; and (3) it must be expected that a change in fair value of the derivative financial instrument and an opposite change in the fair value of the hedged exposure will have a high degree of correlation. Changes in our derivatives’ fair values are recognized in income unless specific hedge accounting and documentation criteria are met (i.e., the instruments are designated and accounted for as hedges). We record the effective portion of the unrealized gains and losses on our derivative financial instruments that are designated as cash flow hedges in the caption "Accumulated other comprehensive income (loss)" in the accompanying consolidated statements of financial position. Any ineffectiveness or excluded portion of a designated cash flow hedge is recognized in income. Upon occurrence of the hedged transaction, the gains and losses on the derivative are recognized in income.
Use Of Estimates	The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying disclosures. We evaluate our estimates on a continuous basis. We base our estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances. The actual amounts may vary from the estimates used in the preparation of the accompanying consolidated financial statements. We have reclassified certain prior period amounts to conform to current period presentation.
Income Taxes	Income Taxes. We provide for income taxes utilizing the asset and liability method of accounting. Under this method, deferred income taxes are recorded to reflect the tax consequences in future years of differences between the tax basis of assets and liabilities and their financial reporting amounts at each balance sheet date, based on enacted tax laws and statutory tax rates applicable to the periods in which the differences are expected to affect taxable income. If it is determined that it is more likely than not that future tax benefits associated with a deferred income tax asset will not be realized, a valuation allowance is provided. The effect of a change in tax rates on deferred income tax assets and liabilities is recognized in the provision for income taxes in the period that includes the enactment date. Beginning in 2017, differences between actual tax benefits realized on employee stock awards and estimated tax benefits at date of grant are adjusted to our provision for income taxes upon vesting or exercise of the stock award. Our provision for income taxes also includes the impact of provisions established for uncertain income tax positions, as well as any related penalties and interest.
Earnings Per Share, Or EPS	Earnings Per Share, or EPS. Basic EPS excludes dilution and is computed by dividing earnings available to common stockholders by the weighted-average number of common shares outstanding for the period. Diluted EPS includes all potential dilutive common stock in the weighted average shares outstanding. For purposes of computing diluted earnings per share for the years ended December 31, 2017 , 2016 and 2015 , respectively, 2 million, 3 million and 4 million shares were assumed to have been outstanding related to common share equivalents. We exclude from the calculation of diluted EPS options with exercise prices that are greater than the average market price and shares related to stock-based awards whose combined exercise price and unamortized fair value were greater in each of those periods than the average market price of our common stock for the period, because their effect would be anti-dilutive. We excluded less than 1 million of anti-dilutive shares in each of 2017 , 2016 and 2015 from our diluted EPS calculation. We include performance stock unit awards in the dilutive potential common shares when they become contingently issuable per the authoritative guidance and exclude the awards when they are not contingently issuable.
Recently Adopted/ New Accounting Pronouncements	Recently Adopted Accounting Pronouncements. Date Issued and Topic Date Adopted and Method Description Impact March 2016 Derivatives and Hedging January 1, 2017 Prospectively This update clarifies the effect of derivative contract novations on existing hedge accounting relationships. As it relates to derivative instruments, novation refers to replacing one of the parties to a derivative instrument with a new party, which may occur for a variety of reasons such as: financial institution mergers, intercompany transactions, an entity exiting a particular derivatives business or relationship, or because of laws or regulatory requirements. The update clarifies that a change in the counterparty to a derivative instrument that has been designated as the hedging instrument does not, in and of itself, require dedesignation of that hedge accounting relationship provided that all other hedge accounting criteria continue to be met. The adoption of this update did not have any effect on our financial condition or results of operations. March 2016 January 1, 2017 Prospectively / Retrospectively This update requires excess tax benefits and tax deficiencies to be recorded to the provision for income taxes in the income statement when the awards vest or are exercised and provides an accounting policy election to account for forfeitures as they occur. The update also clarifies that all cash payments made on an employee’s behalf for withheld shares should be presented as financing activity in the statement of cash flows and cash flows related to excess tax benefits should be classified along with other income tax cash flows as an operating activity. The primary impact of the adoption of this update is that we prospectively reduced our 2017 provision for income taxes and earning per share by $40 million or $0.07, respectively, for the recognition of net excess income tax benefits rather than an increase to additional paid-in capital. We elected to continue to estimate expected forfeitures to determine the stock compensation expense to be recognized each period. We also elected to retrospectively apply the presentation requirements for cash flows related to excess tax benefits for all periods presented, which resulted in an increase to both net cash provided by operating activities and net cash used in financing activities of $24 million and $34 million during 2016 and 2015, respectively. January 2017 Business Combinations January 1, 2017 Prospectively This update clarifies the definition of a business and requires a business to include at least an input and a substantive process that together significantly contribute to the ability to create outputs. The update also states that the definition of a business is not met if substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets. The adoption of this update did not have a material effect on our financial condition or results of operations. January 2017 Goodwill January 1, 2017 Prospectively This update eliminates the need to calculate the implied fair value of goodwill when an impairment is indicated. The update states that goodwill impairment is measured as the excess of a reporting unit’s carrying value over its fair value, not to exceed the carrying amount of goodwill. The adoption of this update did not have any effect on our financial condition or results of operations. New Accounting Pronouncements. Date Issued and Topic Effective Date Description Impact May 2014 January 1, 2018 The new standard, as amended, sets forth a single comprehensive model for recognizing and reporting revenues. The standard also requires additional financial statement disclosures that will enable users to understand the nature, amount, timing and uncertainty of revenues and cash flows relating to customer contracts. The standard allows for two methods of adoption: the full retrospective adoption, which requires the standard to be applied to each prior period presented, or the modified retrospective adoption, which requires the cumulative effect of adoption to be recognized as an adjustment to opening retained earnings in the period of adoption. We will adopt the standard using the modified retrospective method. The most significant impacts of the new standard primarily relate to (1) changes in the method used to measure progress on our application maintenance, consulting and business process services fixed-price contracts, (2) the longer period of amortization for costs to fulfill a contract, as well as (3) the timing of revenue recognition and allocation of purchase price on our software license contracts. We expect the one-time adjustment to opening retained earnings in connection with the adoption of this standard to be an increase of approximately $119 million, after a tax impact of approximately $36 million. February 2016 January 1, 2019 The new standard replaces the existing guidance on leases and requires the lessee to recognize a right-of-use asset and a lease liability for all leases with lease terms equal to or greater than twelve months. For finance leases, the lessee would recognize interest expense and amortization of the right-of-use asset, and for operating leases, the lessee would recognize total lease expense on a straight-line basis. Upon adoption, entities will be required to use a modified retrospective transition which provides for certain practical expedients. Entities are required to apply the new standard at the beginning of the earliest comparative period presented. We expect the requirement to recognize a right-of-use asset and a lease liability for operating leases to have a material impact on the presentation of our consolidated statements of financial position. March 2017 January 1, 2019 This update shortens the amortization period for certain callable debt securities held at a premium to the earliest call date. The amendments do not require an accounting change for securities held at a discount. Upon adoption, entities will be required to use a modified retrospective transition with the cumulative effect adjustment recognized to retained earnings as of the beginning of the period of adoption. We are currently evaluating the effect the amendments will have on our consolidated financial statements and related disclosures. May 2017 Share-based Payment Arrangements January 1, 2018 This update amends the scope of modification accounting for share-based payment arrangements. The amendment requires that an entity will not apply modification accounting to a share-based payment award if the award’s fair value, vesting conditions and classification are the same immediately before and after the modification. Upon adoption, entities will be required to apply this guidance prospectively to an award modified on or after the adoption date. We do not expect the adoption of this update to have a material effect on our financial condition or results of operations. Date Issued and Topic Effective Date Description Impact August 2017 January 1, 2019 This update expands and refines hedge accounting for both financial and nonfinancial hedging strategies to better align hedge accounting with companies’ risk management strategies. The update also amends the presentation and disclosure requirements and changes how companies assess effectiveness of their hedges. Adoption methods will differ by type of hedge. We are currently evaluating the effect the update will have on our consolidated financial statements and related disclosures. February 2018 January 1, 2019 This update provides an option for entities to reclassify stranded tax effects caused by the newly-enacted Tax Cuts and Jobs Act, or Tax Reform Act, from accumulated other comprehensive income to retained earnings. Upon adoption, entities have the option to apply the update retrospectively or in the period of adoption. Early adoption of this update is permitted. We expect to early adopt this update as of January 1, 2018. The adoption is expected to result in an increase of $1 million in accumulated other comprehensive income and a corresponding decrease to opening retained earnings.

Business Combinations (Tables)

Business Combinations (Tables)	12 Months Ended
	Dec. 31, 2017
Other acquisitions [Member]
Business Acquisition [Line Items]
Schedule of intangible assets acquired as part of business combination	The allocations of purchase price to the fair value of the aggregate assets acquired and liabilities assumed were as follows: 2017 2016 Fair Value Weighted Average Useful Life Fair Value Weighted Average Useful Life (in millions) (in millions) Cash $ 8 $ 17 Current assets 47 84 Property, plant and equipment and other noncurrent assets 19 53 Non-deductible goodwill 125 157 Customer relationship intangible assets 147 10.6 years 199 6.6 years Other intangible assets 4 2.4 years 1 3.3 years Current liabilities (50 ) (173 ) Noncurrent liabilities (67 ) (51 ) Purchase price $ 233 $ 287

Realignment Charges (Tables)

Realignment Charges (Tables)	12 Months Ended
	Dec. 31, 2017
Realignment Charges [Abstract]
Realignment Charges	Realignment charges for the year ended December 31, 2017 were as follows: (in millions) Employee separations $ 53 Advisory fees 18 Lease termination costs 1 Total realignment costs $ 72

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2017
Investment [Line Items]
Marketable Securities [Table Text Block]	Our investments were as follows as of December 31: 2017 2016 (in millions) Short-term investments: Trading investment securities $ 25 $ 25 Available-for-sale investment securities 1,972 2,264 Held-to-maturity investment securities 745 40 Time deposits 389 806 Total short-term investments $ 3,131 $ 3,135 Long-term investments: Equity and cost method investments $ 74 $ 62 Held-to-maturity investment securities 161 — Total long-term investments $ 235 $ 62
Schedule of Realized Gain (Loss) [Table Text Block]	Proceeds from sales of available-for-sale investment securities and the gross gains and losses that have been included in earnings as a result of those sales were as follows: 2017 2016 2015 (in millions) Proceeds from sales of available-for-sale investment securities $ 2,922 $ 3,541 $ 782 Gross gains $ 1 $ 5 $ 1 Gross losses (3 ) (4 ) — Net realized (losses) gains on sales of available-for-sale investment securities $ (2 ) $ 1 $ 1
Available-for-sale Securities [Member]
Investment [Line Items]
Unrealized Gain (Loss) on Investments [Table Text Block]	The amortized cost, gross unrealized gains and losses and fair value of our available-for-sale investment securities were as follows at December 31: 2017 Amortized Cost Unrealized Gains Unrealized Losses Fair Value (in millions) U.S. Treasury and agency debt securities $ 667 $ — $ (6 ) $ 661 Corporate and other debt securities 439 — (2 ) 437 Certificates of deposit and commercial paper 450 — — 450 Asset-backed securities 297 — (2 ) 295 Municipal debt securities 130 — (1 ) 129 Total available-for-sale investment securities $ 1,983 $ — $ (11 ) $ 1,972 2016 Amortized Cost Unrealized Gains Unrealized Losses Fair Value (in millions) U.S. Treasury and agency debt securities $ 605 $ — $ (3 ) $ 602 Corporate and other debt securities 407 — (2 ) 405 Certificates of deposit and commercial paper 910 1 — 911 Asset-backed securities 232 — (1 ) 231 Municipal debt securities 116 — (1 ) 115 Total available-for-sale investment securities $ 2,270 $ 1 $ (7 ) $ 2,264
Schedule of Temporary Impairment Losses, Investments [Table Text Block]	The fair value and related unrealized losses of our available-for-sale investment securities in a continuous unrealized loss position for less than 12 months and for 12 months or longer were as follows as of December 31: 2017 Less than 12 Months 12 Months or More Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in millions) U.S. Treasury and agency debt securities $ 519 $ (4 ) $ 124 $ (2 ) $ 643 $ (6 ) Corporate and other debt securities 297 (1 ) 126 (1 ) 423 (2 ) Certificates of deposit and commercial paper 49 — — — 49 — Asset-backed securities 193 (1 ) 94 (1 ) 287 (2 ) Municipal debt securities 107 (1 ) 18 — 125 (1 ) Total $ 1,165 $ (7 ) $ 362 $ (4 ) $ 1,527 $ (11 ) 2016 Less than 12 Months 12 Months or More Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in millions) U.S. Treasury and agency debt securities $ 526 $ (3 ) $ — $ — $ 526 $ (3 ) Corporate and other debt securities 342 (2 ) 1 — 343 (2 ) Certificates of deposit and commercial paper 185 — — — 185 — Asset-backed securities 206 (1 ) 1 — 207 (1 ) Municipal debt securities 88 (1 ) 1 — 89 (1 ) Total $ 1,347 $ (7 ) $ 3 $ — $ 1,350 $ (7 )
Investments Classified by Contractual Maturity Date [Table Text Block]	The contractual maturities of our fixed income available-for-sale investment securities as of December 31, 2017 are set forth in the following table: Amortized Cost Fair Value (in millions) Due within one year $ 590 $ 590 Due after one year up to two years 454 450 Due after two years up to three years 556 551 Due after three years 86 86 Asset-backed securities 297 295 Total available-for-sale investment securities $ 1,983 $ 1,972
Held-to-maturity Securities [Member]
Investment [Line Items]
Unrealized Gain (Loss) on Investments [Table Text Block]	2017 Amortized Unrealized Unrealized Fair (in millions) Short-term investments: Corporate and other debt securities $ 346 $ — $ (1 ) $ 345 Commercial paper 399 — (2 ) 397 Total short-term held-to-maturity investments 745 — (3 ) 742 Long-term investments: Corporate and other debt securities 161 — (1 ) 160 Total held-to-maturity investment securities $ 906 $ — $ (4 ) $ 902 2016 Amortized Unrealized Unrealized Fair (in millions) Short-term investments: Certificates of deposit and commercial paper $ 40 $ — $ — $ 40
Schedule of Temporary Impairment Losses, Investments [Table Text Block]	The fair value and related unrealized losses of held-to-maturity investment securities in a continuous unrealized loss position for less than 12 months and for 12 months or longer were as follows as of December 31, 2017 : Less than 12 Months 12 Months or More Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses (in millions) Corporate and other debt securities $ 473 $ (2 ) $ — $ — $ 473 $ (2 ) Commercial paper 394 (2 ) — — 394 (2 ) Total $ 867 $ (4 ) $ — $ — $ 867 $ (4 )
Investments Classified by Contractual Maturity Date [Table Text Block]	The contractual maturities of our fixed income held-to-maturity investment securities as of December 31, 2017 are set forth in the following table: Amortized Cost Fair Value (in millions) Due within one year $ 745 $ 742 Due after one year up to two years 155 154 Due after two years 6 6 Total held-to-maturity investment securities $ 906 $ 902

Property and Equipment, net (Ta

Property and Equipment, net (Tables)	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment, Net [Abstract]
Schedule of property and equipment	Property and equipment were as follows as of December 31: Estimated Useful Life (Years) 2017 2016 (in millions) Buildings 30 $ 836 $ 823 Computer equipment 3 – 5 364 379 Computer software 3 – 8 594 470 Furniture and equipment 5 – 9 511 431 Land 19 23 Leasehold land lease term 63 63 Capital work-in-progress 145 169 Leasehold improvements Shorter of the lease term or the life of the leased asset 308 266 Sub-total 2,840 2,624 Accumulated depreciation and amortization (1,516 ) (1,313 ) Property and equipment, net $ 1,324 $ 1,311

Goodwill and Intangible Asset33

Goodwill and Intangible Assets, net (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule Of Goodwill	Changes in goodwill by our reportable segments were as follows for the years ended December 31, 2017 and 2016 : Segment January 1, 2017 Goodwill Additions and Adjustments Foreign Currency Translation Adjustments December 31, 2017 (in millions) Financial Services $ 227 $ 27 $ 11 $ 265 Healthcare 2,089 13 4 2,106 Products and Resources (1) 159 72 9 240 Communications, Media and Technology (2) 79 11 3 93 Total goodwill $ 2,554 $ 123 $ 27 $ 2,704 Segment January 1, 2016 Goodwill Additions and Adjustments Foreign Currency Translation Adjustments December 31, 2016 (in millions) Financial Services $ 203 $ 28 $ (4 ) $ 227 Healthcare 2,076 14 (1 ) 2,089 Products and Resources (1) 67 94 (2 ) 159 Communications, Media and Technology (2) 59 21 (1 ) 79 Total goodwill $ 2,405 $ 157 $ (8 ) $ 2,554
Schedule of Finite-Lived Intangible Assets	Components of intangible assets were as follows as of December 31: 2017 Gross Carrying Amount Accumulated Amortization Net Carrying Amount (in millions) Customer relationships $ 1,005 $ (304 ) $ 701 Developed technology 333 (140 ) 193 Indefinite life trademarks 63 — 63 Other 51 (27 ) 24 Total intangible assets $ 1,452 $ (471 ) $ 981 2016 Gross Carrying Amount Accumulated Amortization Net Carrying Amount (in millions) Customer relationships $ 845 $ (219 ) $ 626 Developed technology 332 (96 ) 236 Indefinite life trademarks 63 — 63 Other 48 (22 ) 26 Total intangible assets $ 1,288 $ (337 ) $ 951
Schedule of Indefinite-Lived Intangible Assets	Components of intangible assets were as follows as of December 31: 2017 Gross Carrying Amount Accumulated Amortization Net Carrying Amount (in millions) Customer relationships $ 1,005 $ (304 ) $ 701 Developed technology 333 (140 ) 193 Indefinite life trademarks 63 — 63 Other 51 (27 ) 24 Total intangible assets $ 1,452 $ (471 ) $ 981 2016 Gross Carrying Amount Accumulated Amortization Net Carrying Amount (in millions) Customer relationships $ 845 $ (219 ) $ 626 Developed technology 332 (96 ) 236 Indefinite life trademarks 63 — 63 Other 48 (22 ) 26 Total intangible assets $ 1,288 $ (337 ) $ 951
Schedule Of Estimated Amortization Expense	Estimated amortization related to our existing intangible assets for the next five years is as follows: Year Amount (in millions) 2018 $ 134 2019 131 2020 123 2021 120 2022 105

Accrued Expenses and Other Cu34

Accrued Expenses and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2017
Accrued Expenses And Other Current Liabilities [Abstract]
Accrued Expenses And Other Current Liabilities	Accrued expenses and other current liabilities were as follows as of December 31: 2017 2016 (in millions) Compensation and benefits $ 1,272 $ 1,134 Income taxes 48 10 Professional fees 100 99 Travel and entertainment 32 36 Customer volume and other incentives 289 258 Derivative financial instruments 5 4 Other 325 315 Total accrued expenses and other current liabilities $ 2,071 $ 1,856

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Schedule of short-term debt	The following summarizes our short-term debt balances as of December 31: 2017 2016 Amount Weighted Average Interest Rate Amount Weighted Average Interest Rate (in millions) (in millions) Notes outstanding under revolving credit facility $ 75 4.5 % $ — — % Term loan - current maturities 100 2.4 % 81 1.8 % Total short-term debt $ 175 $ 81
Schedule of long-term debt	The following summarizes our long-term debt balances as of December 31: 2017 2016 (in millions) Term loan, due November 2019 $ 800 $ 881 Less: Current maturities (100 ) (81 ) Deferred financing costs (2 ) (3 ) Long-term debt, net of current maturities $ 698 $ 797
Schedule of debt maturities	The following represents the schedule of maturities of our long-term debt: Year Amounts (in millions) 2018 $ 100 2019 700 $ 800

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Schedule Of Income Before Provision For Income Tax	Income before provision for income taxes shown below is based on the geographic location to which such income is attributed for years ended December 31: 2017 2016 2015 (in millions) United States $ 810 $ 752 $ 739 Foreign 1,845 1,605 1,425 Income before provision for income taxes $ 2,655 $ 2,357 $ 2,164
Schedule Of Components Of Provision For Income Taxes	The provision for income taxes consists of the following components for the years ended December 31: 2017 2016 2015 (in millions) Current: Federal and state $ 767 $ 544 $ 352 Foreign 262 352 314 Total current provision 1,029 896 666 Deferred: Federal and state 102 (44 ) (58 ) Foreign 22 (47 ) (68 ) Total deferred provision (benefit) 124 (91 ) (126 ) Total provision for income taxes $ 1,153 $ 805 $ 540
Reconciliation Between Effective Income Tax Rate and U.S. Federal Statutory Rate	The reconciliation between our effective income tax rate and the U.S. federal statutory rate were as follows for the years ended December 31: 2017 % 2016 % 2015 % (Dollars in millions) Tax expense, at U.S. federal statutory rate $ 929 35.0 $ 825 35.0 $ 757 35.0 State and local income taxes, net of federal benefit 39 1.5 42 1.8 42 2.0 Non-taxable income for Indian tax purposes (216 ) (8.2 ) (203 ) (8.6 ) (201 ) (9.3 ) Rate differential on foreign earnings (76 ) (2.9 ) (55 ) (2.3 ) (34 ) (1.6 ) Net impact related to the Tax Reform Act 617 23.2 — — — — India Cash Remittance — — 238 10.1 — — Recognition of previously unrecognized income tax benefits related to uncertain tax positions (73 ) (2.7 ) (16 ) (0.7 ) (23 ) (1.1 ) Credits and other incentives (37 ) (1.4 ) (57 ) (2.4 ) (23 ) (1.0 ) Other (30 ) (1.1 ) 31 1.3 22 1.0 Total provision for income taxes $ 1,153 43.4 $ 805 34.2 $ 540 25.0
Schedule Of Deferred Tax Assets and Liabilities	The significant components of deferred income tax assets and liabilities recorded on the consolidated statements of financial position were as follows as of December 31: 2017 2016 (in millions) Deferred income tax assets: Net operating losses $ 15 $ 14 Revenue recognition 55 69 Compensation and benefits 125 165 Stock-based compensation 14 25 Minimum alternative tax (MAT) and other credits 369 274 Other accrued expenses 22 161 600 708 Less: valuation allowance (10 ) (10 ) Deferred income tax assets, net 590 698 Deferred income tax liabilities: Depreciation and amortization 209 266 Deferred costs 65 — Other 44 13 Deferred income tax liabilities 318 279 Net deferred income tax assets $ 272 $ 419
Summary Of Changes in Unrecognized Tax Benefits	Changes in unrecognized income tax benefits were as follows for the years ended December 31: 2017 2016 (in millions) Balance, beginning of year $ 151 $ 139 Additions based on tax positions related to the current year 17 11 Additions for tax positions of prior years 2 19 Additions for tax positions of acquired subsidiaries — — Reductions for tax positions due to lapse of statutes of limitations (41 ) (15 ) Reductions for tax positions of prior years (32 ) (1 ) Settlements — — Foreign currency exchange movement — (2 ) Balance, end of year $ 97 $ 151

Derivative Financial Instrume37

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Location And Fair Values Of Derivative Financial Instruments In Our Condensed Consolidated Statements Of Financial Position	The following table provides information on the location and fair values of derivative financial instruments included in our consolidated statement of financial position as of December 31: 2017 2016 Designation of Derivatives Location on Statement of Financial Position Assets Liabilities Assets Liabilities (in millions) Foreign exchange forward contracts - Designated as cash flow hedging instruments Other current assets $ 134 $ — $ 34 $ — Other noncurrent assets 20 — 17 — Total 154 — 51 — Foreign exchange forward contracts - Not designated as cash flow hedging instruments Accrued expenses and other current liabilities — 5 — 4 Total — 5 — 4 Total $ 154 $ 5 $ 51 $ 4
Notional Value Of Outstanding Cash Flow Hedge Contracts By Year Of Maturity And Net Unrealized (Loss) Gain Included In Accumulated Other Comprehensive Income (Loss)	The notional value of our outstanding contracts by year of maturity and the net unrealized gains included in accumulated other comprehensive income (loss) for such contracts were as follows as of December 31: 2017 2016 (in millions) 2017 $ — $ 1,320 2018 1,185 1,020 2019 720 — Total notional value of contracts outstanding $ 1,905 $ 2,340 Net unrealized gains included in accumulated other comprehensive income (loss), net of taxes $ 115 $ 39
Location And Amounts Of Pre-Tax Gains (Losses) On Cash Flow Hedge Derivative Financial Instruments	The following table provides information on the location and amounts of pre-tax gains on our cash flow hedges for the year ended December 31: Change in Derivative Gains Recognized in Accumulated Other Comprehensive Income (Loss) (effective portion) Location of Net Derivative Gains Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (effective portion) Net Gains Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (effective portion) 2017 2016 2017 2016 (in millions) Foreign exchange forward contracts - Designated as cash flow hedging instruments $ 232 $ 83 Cost of revenues $ 109 $ 14 Selling, general and administrative expenses 20 3 Total $ 129 $ 17
Additional Information Related To Outstanding Contracts Not Designated As Hedging Instruments	Additional information related to our outstanding foreign exchange forward contracts not designated as hedging instruments is as follows as of December 31: 2017 2016 Notional Market Value Notional Market Value (in millions) Contracts outstanding $ 255 $ (5 ) $ 213 $ (4 ) The following table provides information on the location and amounts of realized and unrealized pre-tax gains and losses on our other derivative financial instruments for the year ended December 31: Location of Net (Losses) on Derivative Instruments Amount of Net (Losses) on Derivative Instruments 2017 2016 (in millions) Foreign exchange forward contracts - Not designated as hedging instruments Foreign currency exchange gains (losses), net $ (23 ) $ (3 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Financial Assets And (Liabilities) Measured At Fair Value On A Recurring Basis	The following table summarizes our financial assets and (liabilities) measured at fair value on a recurring basis as of December 31, 2017 : Level 1 Level 2 Level 3 Total (in millions) Cash equivalents: Money market funds $ 334 $ — $ — $ 334 Bank deposits — 80 — 80 Commercial paper — 386 — 386 Total cash equivalents 334 466 — 800 Short-term investments: Time deposits — 389 — 389 Available-for-sale investment securities: U.S. Treasury and agency debt securities 585 76 — 661 Corporate and other debt securities — 437 — 437 Certificates of deposit and commercial paper — 450 — 450 Asset-backed securities — 295 — 295 Municipal debt securities — 129 — 129 Total available-for-sale investment securities 585 1,387 — 1,972 Held-to-maturity investment securities: Commercial paper — 397 — 397 Corporate and other debt securities — 345 — 345 Total short-term held-to-maturity investment securities — 742 — 742 Total short-term investments (1) 585 2,518 — 3,103 Long-term investments: Held-to-maturity investment securities: Corporate and other debt securities — 160 — 160 Total long-term held-to-maturity investment securities — 160 — 160 Total long-term investments (2) — 160 — 160 Derivative financial instruments - foreign exchange forward contracts: Other current assets — 134 — 134 Accrued expenses and other current liabilities — (5 ) — (5 ) Other noncurrent assets — 20 — 20 Total $ 919 $ 3,293 $ — $ 4,212 ________________ (1) Excludes trading securities invested in a mutual fund valued at $25 million based on the NAV of the fund at December 31, 2017. (2) Excludes equity and cost method investments of $74 million at December 31, 2017, which are accounted for using the equity method of accounting and at cost, respectively. The following table summarizes our financial assets and (liabilities) measured at fair value on a recurring basis as of December 31, 2016 : Level 1 Level 2 Level 3 Total (in millions) Cash equivalents: Money market funds $ 624 $ — $ — $ 624 Commercial paper — 131 — 131 Total cash equivalents 624 131 — 755 Short-term investments: Time deposits — 806 — 806 Available-for-sale investment securities: U.S. Treasury and agency debt securities 558 44 — 602 Corporate and other debt securities — 405 — 405 Certificates of deposit and commercial paper — 911 — 911 Asset-backed securities — 231 — 231 Municipal debt securities — 115 — 115 Total available-for-sale investment securities 558 1,706 — 2,264 Held-to-maturity investment securities: Certificates of deposit and commercial paper — 40 — 40 Total held-to-maturity investment securities — 40 — 40 Total short-term investments (1) 558 2,552 — 3,110 Derivative financial instruments - foreign exchange forward contracts: Other current assets — 34 — 34 Accrued expenses and other current liabilities — (4 ) — (4 ) Other noncurrent assets — 17 — 17 Total $ 1,182 $ 2,730 $ — $ 3,912

Stockholder's Equity (Tables)

Stockholder's Equity (Tables)	12 Months Ended
	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	Changes in accumulated other comprehensive income (loss) by component were as follows for the year ended December 31, 2017 : 2017 Before Tax Amount Tax Effect Net of Tax Amount (in millions) Foreign currency translation adjustments: Beginning balance $ (149 ) $ — $ (149 ) Change in foreign currency translation adjustments 111 — 111 Ending balance $ (38 ) $ — $ (38 ) Unrealized (losses) on available-for-sale investment securities: Beginning balance $ (6 ) $ 2 $ (4 ) Net unrealized losses arising during the period (7 ) 3 (4 ) Reclassification of net losses to Other, net 2 (1 ) 1 Net change (5 ) 2 (3 ) Ending balance $ (11 ) $ 4 $ (7 ) Unrealized gains on cash flow hedges: Beginning balance $ 51 $ (12 ) $ 39 Unrealized gains arising during the period 232 (57 ) 175 Reclassifications of net (gains) to: Cost of revenues (109 ) 26 (83 ) Selling, general and administrative expenses (20 ) 4 (16 ) Net change 103 (27 ) 76 Ending balance $ 154 $ (39 ) $ 115 Accumulated other comprehensive income (loss): Beginning balance $ (104 ) $ (10 ) $ (114 ) Other comprehensive income (loss) 209 (25 ) 184 Ending balance $ 105 $ (35 ) $ 70 Changes in accumulated other comprehensive income (loss) by component were as follows for the years ended December 31, 2016 and 2015 : 2016 2015 Before Tax Amount Tax Effect Net of Tax Amount Before Tax Tax Net of Tax (in millions) Foreign currency translation adjustments: Beginning balance $ (90 ) $ — $ (90 ) $ (35 ) $ — $ (35 ) Change in foreign currency translation adjustments (59 ) — (59 ) (55 ) — (55 ) Ending balance $ (149 ) $ — $ (149 ) $ (90 ) $ — $ (90 ) Unrealized (losses) on available-for-sale investment securities: Beginning balance $ (7 ) $ 3 $ (4 ) $ (2 ) $ 1 $ (1 ) Net unrealized gains (losses) arising during the period 5 (2 ) 3 (4 ) 1 (3 ) Reclassification of net (gains) to Other, net (4 ) 1 (3 ) (1 ) 1 — Net change 1 (1 ) — (5 ) 2 (3 ) Ending balance $ (6 ) $ 2 $ (4 ) $ (7 ) $ 3 $ (4 ) Unrealized gains (losses) on cash flow hedges: Beginning balance $ (15 ) $ 3 $ (12 ) $ (103 ) $ 16 $ (87 ) Unrealized gains arising during the period 83 (19 ) 64 17 — 17 Reclassifications of net (gains) losses to: Cost of revenues (14 ) 3 (11 ) 59 (11 ) 48 Selling, general and administrative expenses (3 ) 1 (2 ) 12 (2 ) 10 Net change 66 (15 ) 51 88 (13 ) 75 Ending balance $ 51 $ (12 ) $ 39 $ (15 ) $ 3 $ (12 ) Accumulated other comprehensive income (loss): Beginning balance $ (112 ) $ 6 $ (106 ) $ (140 ) $ 17 $ (123 ) Other comprehensive income (loss) 8 (16 ) (8 ) 28 (11 ) 17 Ending balance $ (104 ) $ (10 ) $ (114 ) $ (112 ) $ 6 $ (106 )
Dividends Declared	Dividends on our Class A common stock during the year were as follows: Dividends per Share Amount (in millions) Three months ended June 30, 2017 $ 0.15 $ 89 Three months ended September 30, 2017 0.15 90 Three months ended December 31, 2017 0.15 89 Year ended December 31, 2017 $ 268

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Schedule of future minimum rental payments under non-cancelable operating leases	Future minimum rental payments on our operating leases as of December 31, 2017 are as follows: Operating lease obligation (in millions) 2018 $ 188 2019 178 2020 156 2021 124 2022 87 Thereafter 210 Total minimum lease payments $ 943
Schedule of future minimum payments on capital leases	Future minimum rental payments on our capital leases as of December 31, 2017 are as follows: Capital lease obligation (in millions) 2018 $ 9 2019 6 2020 5 2021 4 2022 4 Thereafter 23 Total minimum lease payments 51 Interest (10 ) Present value of minimum lease payments $ 41

Stock-Based Compensation Plans

Stock-Based Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2017
Share-based Compensation [Abstract]
Schedule Of Allocation Of Total Stock-Based Compensation Expense	The allocation of total stock-based compensation expense between cost of revenues and selling, general and administrative expenses as well as the related income tax benefit were as follows for the three years ended December 31: 2017 2016 2015 (in millions) Cost of revenues $ 55 $ 53 $ 39 Selling, general and administrative expenses 166 164 153 Total stock-based compensation expense $ 221 $ 217 $ 192 Income tax benefit $ 101 $ 49 $ 46
Schedule Of Assumptions Used To Calculate The Fair Value Of Option Grants	The fair values of option grants, including the Purchase Plan, were estimated at the date of grant during the years ended December 31, 2017 , 2016 , and 2015 based upon the following assumptions and were as follows: 2017 2016 2015 Dividend yield 1.0 % 0.0 % 0.0 % Weighted average volatility factor: Stock options 25.9 % 28.3 % 28.1 % Purchase Plan 24.3 % 26.5 % 25.8 % Weighted average expected life (in years): Stock options 4.36 4.46 4.29 Purchase Plan 0.25 0.25 0.25 Weighted average risk-free interest rate: Stock options 1.9 % 1.1 % 1.4 % Purchase Plan 0.9 % 0.4 % 0.1 % Weighted average grant date fair value: Stock options $ 13.06 $ 15.17 $ 16.53 Purchase Plan $ 9.23 $ 8.74 $ 9.04
Summary Of Activity For Stock Options	A summary of the activity for stock options granted under our stock-based compensation plans as of December 31, 2017 and changes during the year then ended is presented below: Number of Options (in millions) Weighted Average Exercise Price (in dollars) Weighted Average Remaining Life (in years) Aggregate Intrinsic Value (in millions) Outstanding at January 1, 2017 2.4 $ 21.08 Granted — — Exercised (1.7 ) 19.76 Cancelled — — Expired — — Outstanding at December 31, 2017 0.7 $ 24.88 1.6 $ 29 Vested and expected to vest at December 31, 2017 0.7 $ 24.78 1.6 $ 29 Exercisable at December 31, 2017 0.7 $ 23.28 1.5 $ 29
Summary Of The Activity For Performance Stock Units	A summary of the activity for PSUs granted under our stock-based compensation plans as of December 31, 2017 and changes during the year then ended is presented below. The presentation reflects the number of PSUs at the maximum performance milestones. Number of Units (in millions) Weighted Average Grant Date Fair Value (in dollars) Unvested at January 1, 2017 2.7 $ 55.24 Granted 2.0 60.77 Vested (0.9 ) 55.07 Forfeited (0.4 ) 56.81 Reduction due to the achievement of lower than maximum performance milestones (0.7 ) 55.04 Unvested at December 31, 2017 2.7 $ 59.15
Summary Of The Activity For Restricted Stock Units	A summary of the activity for RSUs granted under our stock-based compensation plans as of December 31, 2017 and changes during the year then ended is presented below: Number of Units (in millions) Weighted Average Grant Date Fair Value (in dollars) Unvested at January 1, 2017 4.8 $ 56.45 Granted 3.6 67.56 Vested (2.5 ) 56.81 Forfeited (0.7 ) 57.63 Unvested at December 31, 2017 5.2 $ 63.80

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2017
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Revenues From External Customers And Segment Operating Profit	Revenues from external customers and segment operating profit, before unallocated costs, by reportable segment were as follows: 2017 2016 2015 (in millions) Revenues: Financial Services $ 5,636 $ 5,366 $ 5,003 Healthcare 4,263 3,871 3,668 Products and Resources 3,040 2,660 2,344 Communications, Media and Technology 1,871 1,590 1,401 Total revenues $ 14,810 $ 13,487 $ 12,416 Segment Operating Profit: Financial Services $ 1,636 $ 1,707 $ 1,642 Healthcare 1,304 1,153 1,200 Products and Resources 868 851 803 Communications, Media and Technology 565 488 453 Total segment operating profit 4,373 4,199 4,098 Less: unallocated costs 1,892 1,910 1,956 Income from operations $ 2,481 $ 2,289 $ 2,142
Revenues And Long-Lived Assets By Geographic Area	Revenues and long-lived assets, by geographic area, were as follows: 2017 2016 2015 (in millions) Revenues: (1) North America (2) $ 11,450 $ 10,546 $ 9,759 United Kingdom 1,150 1,176 1,188 Rest of Europe 1,248 969 820 Europe - Total 2,398 2,145 2,008 Rest of World (3) 962 796 649 Total $ 14,810 $ 13,487 $ 12,416 2017 2016 2015 (in millions) Long-lived Assets: (4) North America (2) $ 360 $ 279 $ 242 Europe 63 52 32 Rest of World (3)(5) 901 980 997 Total $ 1,324 $ 1,311 $ 1,271 _____________ (1) Revenues are attributed to regions based upon customer location. (2) Substantially all relates to operations in the United States. (3) Includes our operations in Asia Pacific, the Middle East and Latin America. (4) Long-lived assets include property and equipment, net of accumulated depreciation and amortization. (5) Substantially all of these long-lived assets relate to our operations in India.

Quarterly Financial Data (Una43

Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Data [Abstract]
Summary Of Quarterly Financial Data	Summarized quarterly results for the two years ended December 31, 2017 are as follows: Three Months Ended 2017 March 31 June 30 September 30 December 31 Full Year (in millions, except per share data) Revenues $ 3,546 $ 3,670 $ 3,766 $ 3,828 $ 14,810 Cost of revenues (exclusive of depreciation and amortization expense shown separately below) 2,194 2,261 2,337 2,360 9,152 Selling, general and administrative expenses 686 709 674 700 2,769 Depreciation and amortization expense 96 94 107 111 408 Income from operations 570 606 648 657 2,481 Net income (loss) (1) 557 470 495 (18 ) 1,504 Basic earnings (losses) per share (2) (3) $ 0.92 $ 0.80 $ 0.84 $ (0.03 ) $ 2.54 Diluted earnings (losses) per share (2) (3) $ 0.92 $ 0.80 $ 0.84 $ (0.03 ) $ 2.53 Three Months Ended 2016 March 31 June 30 September 30 December 31 Full Year (in millions, except per share data) Revenues $ 3,202 $ 3,370 $ 3,453 $ 3,462 $ 13,487 Cost of revenues (exclusive of depreciation and amortization expense shown separately below) 1,915 2,038 2,077 2,078 8,108 Selling, general and administrative expenses 646 654 701 730 2,731 Depreciation and amortization expense 87 87 92 93 359 Income from operations 554 591 583 561 2,289 Net income 441 252 444 416 1,553 Basic earnings per share (2) $ 0.73 $ 0.42 $ 0.73 $ 0.69 $ 2.56 Diluted earnings per share (2) $ 0.72 $ 0.41 $ 0.73 $ 0.68 $ 2.55 ____________________________ (1) The net loss for the quarter ended December 31, 2017, includes the one-time provisional incremental income tax expense relating to the Tax Reform Act. See Note 10 to our consolidated financial statements. (2) The sum of the quarterly basic and diluted earnings (losses) per share for each of the four quarters may not equal the earnings (losses) per share for the year due to rounding. (3) In March 2016, the FASB issued an update related to stock compensation. The update simplified the accounting for excess tax benefits and deficiencies related to employee stock-based payment transactions. We adopted this standard prospectively on January 1, 2017. For the first, second, third and fourth quarters of 2017, we recognized net excess tax benefits on stock-based compensation awards in our income tax provision in the amount of $6 million , $5 million , $5 million and $24 million , respectively. This impacted our earnings per shares in the first, second, third and fourth quarters of 2017 by $0.01 , $0.01 , $0.01 and $0.04 per share, respectively. In prior periods, such net excess tax benefits were recorded in additional paid in capital.

Business Description and Summ44

Business Description and Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Leasehold for land lease terms, maximum years	99 years
Amount of Deferred Costs Related to Long-term Contracts	$ 267	$ 188
Dilutive effect of shares issuable under stock-based compensation plans	2	3	4
Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share - less than	1	1	1

Business Description and Summ45

Business Description and Summary of Significant Accounting Policies Accounting Standard Updates (Details) - Pro Forma [Member] - Accounting Standards Update 2014-09 [Member] $ in Millions	Mar. 31, 2018USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative Tax Effect Of New Accounting Principle In Period Of Adoption	$ 36
Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption	$ 119

Business Description and Summ46

Business Description and Summary of Significant Accounting Policies Net Excess Tax Benefits on Stock-based Compensation Awards (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended				12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounting Standards Update [Abstract]
Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount	$ 24	$ 5	$ 5	$ 6	$ 40	$ 24	$ 34
Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Per Share Amount	$ 0.04	$ 0.01	$ 0.01	$ 0.01	$ 0.07

Internal Investigation and Re47

Internal Investigation and Related Matters (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Loss Contingencies [Line Items]
Selling, general and administrative expenses	$ 700	$ 674	$ 709	$ 686	$ 730	$ 701	$ 654	$ 646	$ 2,769	$ 2,731	$ 2,509
Decrease in depreciation and amortization expense	(111)	$ (107)	$ (94)	$ (96)	(93)	(92)	$ (87)	$ (87)	(408)	(359)	(325)
Property and equipment, net	1,324				1,311				1,324	1,311	$ 1,271
Internal Investigation and Related Matters [Member]
Loss Contingencies [Line Items]
Potential Improper Payments	6								6
Potential Improper Payments Remaining Under Investigation	$ 2								$ 2
Out of period adjustment [Member] | Internal Investigation and Related Matters [Member]
Loss Contingencies [Line Items]
Selling, general and administrative expenses					$ 1	$ 3				$ 4

Business Combinations (Narrativ

Business Combinations (Narrative) (Details) - Other acquisitions [Member] $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)business	Dec. 31, 2016USD ($)business	Dec. 31, 2015business
Business Acquisition [Line Items]
Number of business combinations | business	5	8	0
Total consideration | $	$ 233	$ 287

Business Combinations Allocatio

Business Combinations Allocation of Purchase Price (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Goodwill	$ 2,704	$ 2,554	$ 2,405
Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years 7 months 6 days	6 years 7 months 6 days
Other Intangible Assets [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	2 years 4 months 24 days	3 years 3 months 18 days
Other acquisitions [Member]
Business Acquisition [Line Items]
Cash	$ 8	$ 17
Current assets	47	84
Property, plant and equipment and other noncurrent assets	19	53
Goodwill	125	157
Current liabilities	(50)	(173)
Noncurrent liabilities	(67)	(51)
Purchase price	233	287
Other acquisitions [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Intangible assets acquired	147	199
Other acquisitions [Member] | Other Intangible Assets [Member]
Business Acquisition [Line Items]
Intangible assets acquired	$ 4	$ 1

Realignment Charges (Details)

Realignment Charges (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Selling, general and administrative expenses
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	$ 72	$ 0	$ 0
Special Termination Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	53
Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	18
Facility Closing [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	$ 1

Investments Short-term investme

Investments Short-term investments (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Short-term Investments [Abstract]
Trading investment securities	$ 25	$ 25
Available-for-sale Securities, Current	1,972	2,264
Held-to-maturity Securities, Current	745	40
Other Marketable Securities, Current	389	806
Short-term Investments	$ 3,131	$ 3,135

Investments Long-term investmen

Investments Long-term investments (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Long-term Investments [Abstract]
Equity and Cost Method Investments	$ 74	$ 62
Held-to-maturity Securities, Noncurrent	161	0
Long-term Investments	$ 235	$ 62

Investments Trading Securities

Investments Trading Securities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities, Unrealized Holding Loss	$ 1	$ 1
Trading investment securities	25	25
Trading Securities, Realized Gain (Loss)	$ 0	$ 0

Investments Available-for-sale

Investments Available-for-sale securities - amortized cost, gross unrealized gains and losses and fair value (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 1,983	$ 2,270
Gains	0	1
Losses	11	7
Fair Value	1,972	2,264
U.S. Treasury And Agency Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	667	605
Gains	0	0
Losses	6	3
Fair Value	661	602
Corporate And Other Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	439	407
Gains	0	0
Losses	2	2
Fair Value	437	405
Commercial Paper and Certificates of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	450	910
Gains	0	1
Losses	0	0
Fair Value	450	911
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	297	232
Gains	0	0
Losses	2	1
Fair Value	295	231
Municipal Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	130	116
Gains	0	0
Losses	1	1
Fair Value	$ 129	$ 115

Investments Available-for-sal55

Investments Available-for-sale securities in a continuous unrealized loss position (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	$ 1,165	$ 1,347
Unrealized losses, less than 12 months	7	7
Fair value, 12 months or more	362	3
Unrealized losses, 12 months or more	4	0
Total fair value	1,527	1,350
Total unrealized loss	11	7
U.S. Treasury And Agency Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	519	526
Unrealized losses, less than 12 months	4	3
Fair value, 12 months or more	124	0
Unrealized losses, 12 months or more	2	0
Total fair value	643	526
Total unrealized loss	6	3
Corporate And Other Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	297	342
Unrealized losses, less than 12 months	1	2
Fair value, 12 months or more	126	1
Unrealized losses, 12 months or more	1	0
Total fair value	423	343
Total unrealized loss	2	2
Commercial Paper and Certificates of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	49	185
Unrealized losses, less than 12 months	0	0
Fair value, 12 months or more	0	0
Unrealized losses, 12 months or more	0	0
Total fair value	49	185
Total unrealized loss	0	0
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	193	206
Unrealized losses, less than 12 months	1	1
Fair value, 12 months or more	94	1
Unrealized losses, 12 months or more	1	0
Total fair value	287	207
Total unrealized loss	2	1
Municipal Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value, less than 12 months	107	88
Unrealized losses, less than 12 months	1	1
Fair value, 12 months or more	18	1
Unrealized losses, 12 months or more	0	0
Total fair value	125	89
Total unrealized loss	$ 1	$ 1

Investments Available-for-sal56

Investments Available-for-sale securities - contractual maturities (Details) $ in Millions	Dec. 31, 2017USD ($)
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Rolling Maturity [Abstract]
Due within one year	$ 590
Due after one year up to two years	454
Due after two years up to three years	556
Due after three years	86
Asset-backed securities	297
Amortized Cost	1,983
Available-for-sale Securities, Debt Maturities, Fair Value, Rolling Maturity [Abstract]
Due within one year	590
Due after one year up to two years	450
Due after two years up to three years	551
Due after three years	86
Asset-backed securities	295
Fair value	$ 1,972

Investments Available-for-sal57

Investments Available-for-sale securities - proceeds from sales, gross gains and losses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Proceeds from Sale of Available-for-sale Securities	$ 2,922	$ 3,541	$ 782
Gross Gains	1	5	1
Gross Losses	3	4	0
Net realized (losses) gains on sales of available-for-sale investment securities	$ (2)	$ 1	$ 1

Investments Held-to-maturity se

Investments Held-to-maturity securities - amortized cost, gross unrealized gains and losses and fair value (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost, Current	$ 745	$ 40
Unrealized gains	0
Unrealized Losses	(4)
Fair Value	902
Amortized Cost, Noncurrent	161	0
Held-to-maturity Securities	906
Short-term Investments [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost, Current	745
Unrealized gains	0
Unrealized Losses	(3)
Fair Value	742
Commercial Paper and Certificates of Deposit [Member] | Short-term Investments [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost, Current		40
Unrealized gains		0
Unrealized Losses		0
Fair Value		$ 40
Corporate And Other Debt Securities [Member] | Long-term investments [Member]
Schedule of Held-to-maturity Securities [Line Items]
Unrealized gains	0
Unrealized Losses	(1)
Fair Value	160
Amortized Cost, Noncurrent	161
Corporate And Other Debt Securities [Member] | Short-term Investments [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost, Current	346
Unrealized gains	0
Unrealized Losses	(1)
Fair Value	345
Commercial Paper [Member] | Short-term Investments [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost, Current	399
Unrealized gains	0
Unrealized Losses	(2)
Fair Value	$ 397

Investments Held-to-maturity 59

Investments Held-to-maturity securities in a continuous unrealized loss position (Details) $ in Millions	Dec. 31, 2017USD ($)
Schedule of Held-to-maturity Securities [Line Items]
Fair value, less than 12 months	$ 867
Unrealized losses, less than 12 months	(4)
Fair value, 12 months or more	0
Unrealized losses, 12 months or more	0
Total fair value	867
Total unrealized losses	(4)
Corporate And Other Debt Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Fair value, less than 12 months	473
Unrealized losses, less than 12 months	(2)
Fair value, 12 months or more	0
Unrealized losses, 12 months or more	0
Total fair value	473
Total unrealized losses	(2)
Commercial Paper [Member]
Schedule of Held-to-maturity Securities [Line Items]
Fair value, less than 12 months	394
Unrealized losses, less than 12 months	(2)
Fair value, 12 months or more	0
Unrealized losses, 12 months or more	0
Total fair value	394
Total unrealized losses	$ (2)

Investments Held-to-maturity 60

Investments Held-to-maturity securities - contractual maturities (Details) $ in Millions	Dec. 31, 2017USD ($)
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost, due within one year	$ 745
Fair value, due within one year	742
Amortized cost, due after one year up to two years	155
Fair value, due after one year up to two years	154
Amortized cost, due after two years	6
Fair value, due after two years	6
Held-to-maturity Securities	906
Held-to-maturity Securities, Fair Value	$ 902

Investments Equity Method Inves

Investments Equity Method Investments (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Apr. 30, 2016
Equity Method Investment, Financial Statement, Reported Amounts [Abstract]
Equity Method Investments	$ 67	$ 57
Equity Method Investment, Ownership Percentage			49.00%

Investments Cost Method Investm

Investments Cost Method Investments (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Investments, All Other Investments [Abstract]
Cost Method Investments	$ 7	$ 5

Property and Equipment, net (Na

Property and Equipment, net (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Capital Leased Assets, Gross	$ 44	$ 37
Capitalized Computer Software, Net	40	33
Property, Plant and Equipment [Member]
Depreciation	$ 313	$ 266	$ 233

Property and Equipment, net (Sc

Property and Equipment, net (Schedule Of Property And Equipment, Net) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	$ 2,840	$ 2,624
Accumulated depreciation and amortization	(1,516)	(1,313)
Property and Equipment, net	$ 1,324	1,311	$ 1,271
Buildings [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	30 years
Property and Equipment, gross	$ 836	823
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	$ 364	379
Computer Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	3 years
Computer Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years
Computer Software [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	$ 594	470
Computer Software [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	3 years
Computer Software [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	8 years
Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	$ 511	431
Furniture and Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years
Furniture and Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	9 years
Land [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	$ 19	23
Leasehold Land [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	63	63
Capital Work-in-Progress [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	145	169
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	$ 308	$ 266

Goodwill and Intangible Asset65

Goodwill and Intangible Assets, net (Schedule Of Goodwill Allocation By Reportable Segments) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Roll Forward]
Goodwill, Beginning Balance	$ 2,554	$ 2,405
Additions	123	157
Foreign currency translation adjustments	27	(8)
Goodwill, Ending Balance	2,704	2,554
Financial Services
Goodwill [Roll Forward]
Goodwill, Beginning Balance	227	203
Additions	27	28
Foreign currency translation adjustments	11	(4)
Goodwill, Ending Balance	265	227
Healthcare
Goodwill [Roll Forward]
Goodwill, Beginning Balance	2,089	2,076
Additions	13	14
Foreign currency translation adjustments	4	(1)
Goodwill, Ending Balance	2,106	2,089
Products and Resources
Goodwill [Roll Forward]
Goodwill, Beginning Balance	159	67
Additions	72	94
Foreign currency translation adjustments	9	(2)
Goodwill, Ending Balance	240	159
Communications, Media and Technology
Goodwill [Roll Forward]
Goodwill, Beginning Balance	79	59
Additions	11	21
Foreign currency translation adjustments	3	(1)
Goodwill, Ending Balance	$ 93	$ 79

Goodwill and Intangible Asset66

Goodwill and Intangible Assets, net (Schedule Of Components For Intangible Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization	$ (471)	$ (337)
Intangible Assets, Gross (Excluding Goodwill)	1,452	1,288
Intangible assets, net	981	951
Indefinite life trademarks	63	63
Amortization of intangibles	130	113	$ 97
Amortization Expense Recorded As A Reduction Of Revenues	35	20	$ 5
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,005	845
Accumulated amortization	(304)	(219)
Net carrying amount	701	626
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	333	332
Accumulated amortization	(140)	(96)
Net carrying amount	193	236
Other [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	51	48
Accumulated amortization	(27)	(22)
Net carrying amount	$ 24	$ 26

Goodwill and Intangible Asset67

Goodwill and Intangible Assets, net (Schedule Of Estimated Amortization Expense) (Details) $ in Millions	Dec. 31, 2017USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2,018	$ 134
2,019	131
2,020	123
2,021	120
2,022	$ 105

Accrued Expenses and Other Cu68

Accrued Expenses and Other Current Liabilities (Accrued Expenses And Other Current Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Accrued Expenses And Other Current Liabilities [Abstract]
Compensation and benefits	$ 1,272	$ 1,134
Income taxes	48	10
Professional fees	100	99
Travel and entertainment	32	36
Customer volume and other incentives	289	258
Derivative financial instruments	5	4
Other	325	315
Accrued expenses and other current liabilities	$ 2,071	$ 1,856

Debt (Details)

Debt (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)
Term Loan and Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum debt to equity ratio under covenants	0.40
Term Loan and Revolving Credit Facility [Member] | Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.00%
Term Loan and Revolving Credit Facility [Member] | Minimum [Member] | Eurocurrency [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.75%
Term Loan and Revolving Credit Facility [Member] | Minimum [Member] | Eurocurrency Without Debt Ratings [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.875%
Term Loan and Revolving Credit Facility [Member] | Maximum [Member] | Eurocurrency [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.125%
Term Loan and Revolving Credit Facility [Member] | Maximum [Member] | Eurocurrency Without Debt Ratings [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Term Loan [Member]
Debt Instrument [Line Items]
Principal amount of debt	$ 1,000
Interest rate at period end	2.40%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity	$ 750
Line of Credit Facility, Maximum Period Drawn Notes Have Been Outstanding	90 days

Debt (Short-Term Debt (Details)

Debt (Short-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Short-term Debt [Line Items]
Total short-term debt	$ 175	$ 81
Revolving Credit Facility [Member]
Short-term Debt [Line Items]
Notes drawn under Revolving Facility	$ 75	$ 0
Weighted average interest rate	4.50%	0.00%
Term Loan [Member]
Short-term Debt [Line Items]
Weighted average interest rate	2.40%	1.80%
Term Loan - Current Maturities	$ 100	$ 81

Debt (Long-Term Debt) (Details)

Debt (Long-Term Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term debt	$ 800
Long-term debt, net of current maturities	698	$ 797
Term Loan [Member]
Debt Instrument [Line Items]
Long-term debt	800	881
Less: Current portion	(100)	(81)
Long-term debt, net of current maturities	698	797
Term Loan and Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Net	$ (2)	$ (3)

Debt (Debt Maturities) (Details

Debt (Debt Maturities) (Details) $ in Millions	Dec. 31, 2017USD ($)
Debt Disclosure [Abstract]
2,018	$ 100
2,019	700
Long-term debt	$ 800

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	May 31, 2016	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)		$ 617
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Income Tax Expense		635
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Foreign and U.S. State Tax Applicable Upon Repatriation of the Accumulated Undistributed Foreign Earnings, Provisional Income Tax Expense		53
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Deferred Tax Liability, Provisional Income Tax Benefit		71
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Liability, Current		51	$ 51
Income Tax Expense (Benefit)			1,153	$ 805	$ 540
Deferred income taxes related to MAT		278	$ 278	$ 286
Minimum alternative tax, expiration period (in years)			15 years	10 years
Incentive period for SEZs, years			15 years
Regular corporate income tax rate in India			34.60%
Minimum alternative tax, rate			21.30%
Income tax holiday, increase in net income			$ 217	$ 203	$ 201
Increase in diluted EPS			$ 0.36	$ 0.33	$ 0.33
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Percent			21.00%
Accrued interest and penalties		8	$ 8	$ 7
India
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Unrepatriated foreign earnings		4,082	4,082
Foreign Tax Authority [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Net operating loss carryforward		38	38
Internal Revenue Service (IRS) [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Net operating loss carryforward		$ 12	$ 12
India Cash Remittance [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Foreign Earnings Repatriated	$ 2,800
Income Tax Expense (Benefit)				$ 238
India Cash Remittance [Member] | UNITED STATES
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Foreign Earnings Repatriated	1,200
Foreign Earnings Repatriated, Net of Tax	1,000
India Cash Remittance [Member] | Non-US [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Foreign Earnings Repatriated	$ 1,600

Income Taxes (Schedule Of Incom

Income Taxes (Schedule Of Income Before Provision For Income Tax) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
United States	$ 810	$ 752	$ 739
Foreign	1,845	1,605	1,425
Income before provision for income taxes	$ 2,655	$ 2,357	$ 2,164

Income Taxes (Schedule Of Compo

Income Taxes (Schedule Of Components Of Provision For Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current:
Federal and state	$ 767	$ 544	$ 352
Foreign	262	352	314
Total current provision	1,029	896	666
Deferred:
Federal and state	102	(44)	(58)
Foreign	22	(47)	(68)
Total deferred provision (benefit)	124	(91)	(126)
Total provision for income taxes	$ 1,153	$ 805	$ 540

Income Taxes (Reconciliation Be

Income Taxes (Reconciliation Between Effective Income Tax Rate And U.S. Federal Statutory Rate) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Tax expense, at U.S. federal statutory rate, amount	$ 929	$ 825	$ 757
State and local income taxes, net of federal benefit, amount	39	42	42
Non-taxable income for Indian tax purposes, amount	(216)	(203)	(201)
Rate differential on foreign earnings, amount	(76)	(55)	(34)
Net impact related to the Tax Reform Act	617	0	0
Credits and other incentives, amount	(37)	(57)	(23)
Other adjustments, amount	(30)	31	22
Total provision for income taxes	$ 1,153	$ 805	$ 540
Tax expense, at U.S. federal statutory rate, percentage	35.00%	35.00%	35.00%
State and local income taxes, net of federal benefit, percentage	1.50%	1.80%	2.00%
Non-taxable income for Indian tax purposes, percentage	(8.20%)	(8.60%)	(9.30%)
Rate differential on foreign earnings, percentage	(2.90%)	(2.30%)	(1.60%)
Net impact related to the Tax Reform Act, percentage	23.20%	0.00%	0.00%
Credits and other incentives, percent	(1.40%)	(2.40%)	(1.00%)
Other adjustments, percent	(1.10%)	1.30%	1.00%
Total provision for income taxes, percentage	43.40%	34.20%	25.00%
India Cash Remittance [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Other adjustments, amount	$ 0	$ 238	$ 0
Total provision for income taxes		$ 238
Other adjustments, percent	0.00%	10.10%	0.00%
Recognition of previously unrecognized income tax benefits related to uncertain tax positions [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Other adjustments, amount	$ (73)	$ (16)	$ (23)
Other adjustments, percent	(2.70%)	(0.70%)	(1.10%)

Income Taxes (Schedule Of Defer

Income Taxes (Schedule Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Deferred income tax assets:
Net operating losses	$ 15	$ 14
Revenue recognition	55	69
Compensation and benefits	125	165
Stock-based compensation	14	25
Minimum alternative tax (MAT) and other credits	369	274
Other accrued expenses	22	161
Deferred income tax assets, gross	600	708
Less valuation allowance	(10)	(10)
Deferred income tax assets, net	590	698
Deferred income tax liabilities:
Depreciation and amortization	209	266
Deferred Tax Liabilities, Deferred Expense	65	0
Other	44	13
Deferred income tax liabilities	318	279
Net deferred income tax assets	$ 272	$ 419

Income Taxes (Summary Of Change

Income Taxes (Summary Of Changes In Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Changes in unrecognized income tax benefits
Balance, beginning of year	$ 151	$ 139
Additions based on tax positions related to the current year	17	11
Additions for tax positions of prior years	2	19
Unrecognized Tax Benefits, Increase Resulting from Acquisition	0	0
Reductions for tax positions due to lapse of statutes of limitations	(41)	(15)
Reductions for tax positions of prior years	(32)	(1)
Settlements	0	0
Foreign currency exchange movement	0	(2)
Balance, end of year	$ 97	$ 151

Derivative Financial Instrume79

Derivative Financial Instruments (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Cash flow hedge losses expected to be reclassified to earnings within the next 12 months	$ 100
Cash flow hedge ineffectiveness is immaterial	Hedge ineffectiveness was immaterial for all periods presented.

Derivative Financial Instrume80

Derivative Financial Instruments (Location And Fair Values Of Derivative Financial Instruments In Our Consolidated Statement Of Financial Position) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative assets fair value	$ 154	$ 51
Derivative liabilities fair value	5	4
Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member] | Foreign Exchange Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative assets fair value	154	51
Derivative liabilities fair value	0	0
Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member] | Foreign Exchange Forward Contracts [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets fair value	134	34
Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member] | Foreign Exchange Forward Contracts [Member] | Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets fair value	20	17
Other Derivatives [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative assets fair value	0	0
Derivative liabilities fair value	5	4
Other Derivatives [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Forward Contracts [Member] | Accrued Expenses And Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities fair value	$ 5	$ 4

Derivative Financial Instrume81

Derivative Financial Instruments (Notional Value Of Outstanding Cash Flow Hedge Contracts By Year Of Maturity And Net Unrealized (Loss) Gain Included In Accumulated Other Comprehensive Income) (Details) - Cash Flow Hedges [Member] - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Foreign Exchange Forward Contracts [Member]
Derivative [Line Items]
Derivative, notional amount	$ 1,905	$ 2,340
Net unrealized gains included in accumulated other comprehensive income (loss), net of taxes	115	39
Foreign Exchange Forward, Maturity 2017 [Member]
Derivative [Line Items]
Derivative, notional amount	0	1,320
Foreign Exchange Forward, Maturity 2018 [Member] [Member]
Derivative [Line Items]
Derivative, notional amount	1,185	1,020
Foreign Exchange Forward, Maturity 2019 [Member]
Derivative [Line Items]
Derivative, notional amount	$ 720	$ 0

Derivative Financial Instrume82

Derivative Financial Instruments (Location And Amounts Of Pre-Tax Gains (Losses) On Cash Flow Hedge Derivatives Financial Instruments) (Details) - Cash Flow Hedges [Member] - Designated as Hedging Instrument [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ 129	$ 17
Cost of revenues
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	109	14
Selling, general and administrative expenses
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	20	3
Foreign Exchange Forward Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
(Increase) Decrease in Derivative Losses Recognized in Accumulated Other Comprehensive Income (Loss) (effective portion)	$ 232	$ 83

Derivative Financial Instrume83

Derivative Financial Instruments (Additional Information Related To Outstanding Contracts Not Designated As Hedging Instruments) (Details) - Not Designated as Hedging Instrument [Member] - Foreign Exchange Forward Contracts [Member] - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Derivative, notional amount	$ 255	$ 213
Market value	$ (5)	$ (4)

Derivative Financial Instrume84

Derivative Financial Instruments (Location And Amounts Of Pre-Tax Gains (Losses) On Derivative Financial Instruments Not Designated As Hedges) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Not Designated as Hedging Instrument [Member] | Foreign Exchange Forward Contracts [Member] | Foreign Currency Gain (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of net gains (losses) on derivative instruments	$ (23)	$ (3)

Fair Value Measurements (Financ

Fair Value Measurements (Financial Assets And (Liabilities) Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading investment securities	$ 25	$ 25
Equity and Cost Method Investments	74	62
Held-to-maturity Securities, Fair Value	902
Mutual Fund [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading investment securities	25	25
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	800	755
Time Deposits, Fair Value Disclosure	389	806
Available-for-sale Securities	1,972	2,264
Fair Value Assets And Liabilities Measured On Recurring Basis	4,212	3,912
Fair Value, Measurements, Recurring [Member] | Other Current Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	134	34
Fair Value, Measurements, Recurring [Member] | Accrued Expenses And Other Current Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign Currency Contracts, Liability, Fair Value Disclosure	5	4
Fair Value, Measurements, Recurring [Member] | Other Noncurrent Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	20	17
Fair Value, Measurements, Recurring [Member] | Municipal Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	129	115
Fair Value, Measurements, Recurring [Member] | U.S. Treasury And Agency Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	661	602
Fair Value, Measurements, Recurring [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	437	405
Fair Value, Measurements, Recurring [Member] | Commercial Paper and Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	450	911
Fair Value, Measurements, Recurring [Member] | Asset-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	295	231
Fair Value, Measurements, Recurring [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	334	624
Fair Value, Measurements, Recurring [Member] | Bank Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	80
Fair Value, Measurements, Recurring [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	386	131
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	334	624
Time Deposits, Fair Value Disclosure	0	0
Available-for-sale Securities	585	558
Fair Value Assets And Liabilities Measured On Recurring Basis	919	1,182
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Other Current Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Accrued Expenses And Other Current Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign Currency Contracts, Liability, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Other Noncurrent Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Municipal Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Treasury And Agency Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	585	558
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial Paper and Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Asset-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	334	624
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	466	131
Time Deposits, Fair Value Disclosure	389	806
Available-for-sale Securities	1,387	1,706
Fair Value Assets And Liabilities Measured On Recurring Basis	3,293	2,730
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Other Current Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	134	34
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Accrued Expenses And Other Current Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign Currency Contracts, Liability, Fair Value Disclosure	5	4
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Other Noncurrent Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	20	17
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Municipal Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	129	115
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Treasury And Agency Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	76	44
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	437	405
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial Paper and Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	450	911
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Asset-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	295	231
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Bank Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	80
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	386	131
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Time Deposits, Fair Value Disclosure	0	0
Available-for-sale Securities	0	0
Fair Value Assets And Liabilities Measured On Recurring Basis	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Other Current Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Accrued Expenses And Other Current Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign Currency Contracts, Liability, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Other Noncurrent Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign Currency Contract, Asset, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Municipal Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Treasury And Agency Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial Paper and Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Asset-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	0	0
Long-term investments [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	160
Long-term investments [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	160
Investments, Fair Value Disclosure	160
Long-term investments [Member] | Fair Value, Measurements, Recurring [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	160
Long-term investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	0
Investments, Fair Value Disclosure	0
Long-term investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	0
Long-term investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	160
Investments, Fair Value Disclosure	160
Long-term investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	160
Long-term investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	0
Investments, Fair Value Disclosure	0
Long-term investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	0
Short-term Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	742
Short-term Investments [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	397
Short-term Investments [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	345
Short-term Investments [Member] | Commercial Paper and Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value		40
Short-term Investments [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	742	40
Investments, Fair Value Disclosure	3,103	3,110
Short-term Investments [Member] | Fair Value, Measurements, Recurring [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	397	40
Short-term Investments [Member] | Fair Value, Measurements, Recurring [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	345
Short-term Investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	0	0
Investments, Fair Value Disclosure	585	558
Short-term Investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	0	0
Short-term Investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	0
Short-term Investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	742	40
Investments, Fair Value Disclosure	2,518	2,552
Short-term Investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	397	40
Short-term Investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	345
Short-term Investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	0	0
Investments, Fair Value Disclosure	0	0
Short-term Investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	0	$ 0
Short-term Investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate And Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity Securities, Fair Value	$ 0

Stockholder's Equity Share Repu

Stockholder's Equity Share Repurchase Program (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Authorized Amount	$ 3,500
Stock Repurchase Program, Remaining Authorized Repurchase Amount	1,700
Repurchases of common stock	$ 1,889	$ 512	$ 460
Share Repurchases, Other [Member]
Equity, Class of Treasury Stock [Line Items]
Stock Repurchased During Period, Shares	1.3	1.2	1.3
Repurchases of common stock	$ 89	$ 72	$ 84

Stockholder's Equity Accelerate

Stockholder's Equity Accelerated Share Repurchases (Details) - USD ($) shares in Millions, $ in Millions	1 Months Ended	6 Months Ended	12 Months Ended
	Dec. 31, 2017	Aug. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Mar. 31, 2017
Accelerated Share Repurchases [Line Items]
Repurchases of common stock			$ 1,889	$ 512	$ 460
March ASR
Accelerated Share Repurchases [Line Items]
Accelerated Share Repurchases, Settlement (Payment) or Receipt						$ (1,500)
Accelerated Share Repurchases, Number of Shares Delivered		23.7
December ASR
Accelerated Share Repurchases [Line Items]
Accelerated Share Repurchases, Settlement (Payment) or Receipt	$ (300)		(300)
Accelerated Share Repurchases, Number of Shares Delivered	3.6
Common Stock Including Additional Paid in Capital [Member]
Accelerated Share Repurchases [Line Items]
Repurchases of common stock			630
Retained Earnings [Member]
Accelerated Share Repurchases [Line Items]
Repurchases of common stock			$ 1,170

Stockholder's Equity Dividends

Stockholder's Equity Dividends (Details) - USD ($) $ / shares in Units, $ in Millions	Feb. 05, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Dividends Payable [Line Items]
Dividends declared per common share					$ 0.45	$ 0	$ 0
Common Stock, Dividends, Per Share, Cash Paid		$ 0.15	$ 0.15	$ 0.15
Dividends, Common Stock, Cash		$ 89	$ 90	$ 89	$ 268
Scenario, Forecast [Member]
Dividends Payable [Line Items]
Dividends declared per common share	$ 0.20

Stockholder's Equity Accumulate

Stockholder's Equity Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCI, beginning balance	$ 10,728	$ 9,278	$ 7,740
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Other comprehensive income (loss)	184	(8)	17
AOCI, ending balance	10,669	10,728	9,278
Foreign currency translation adjustments:
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCI before Tax, beginning balance	(149)	(90)	(35)
AOCI Tax, beginning balance	0	0	0
AOCI, beginning balance	(149)	(90)	(35)
Other Comprehensive Income (Loss), before Tax [Abstract]
Other Comprehensive Income (Loss), before Tax	111	(59)	(55)
Other Comprehensive Income (Loss), Tax [Abstract]
Other Comprehensive Income (Loss), Tax	0	0	0
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Other comprehensive income (loss)	111	(59)	(55)
AOCI before Tax, ending balance	(38)	(149)	(90)
AOCI Tax, ending balance	0	0	0
AOCI, ending balance	(38)	(149)	(90)
Unrealized (losses) on available-for-sale investment securities:
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCI before Tax, beginning balance	(6)	(7)	(2)
AOCI Tax, beginning balance	2	3	1
AOCI, beginning balance	(4)	(4)	(1)
Other Comprehensive Income (Loss), before Tax [Abstract]
OCI, before Reclassifications, before Tax	(7)	5	(4)
Reclassification from AOCI, Current Period, before Tax	2	(4)	(1)
Other Comprehensive Income (Loss), before Tax	(5)	1	(5)
Other Comprehensive Income (Loss), Tax [Abstract]
Other Comprehensive Income (Loss) before Reclassifications, Tax	3	(2)	1
Reclassification from AOCI, Current Period, Tax	(1)	1	1
Other Comprehensive Income (Loss), Tax	2	(1)	2
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
OCI, before Reclassifications, Net of Tax	(4)	3	(3)
Reclassification from AOCI, Current Period, Net of Tax	1	(3)	0
Other comprehensive income (loss)	(3)	0	(3)
AOCI before Tax, ending balance	(11)	(6)	(7)
AOCI Tax, ending balance	4	2	3
AOCI, ending balance	(7)	(4)	(4)
Unrealized gains on cash flow hedges:
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCI before Tax, beginning balance	51	(15)	(103)
AOCI Tax, beginning balance	(12)	3	16
AOCI, beginning balance	39	(12)	(87)
Other Comprehensive Income (Loss), before Tax [Abstract]
OCI, before Reclassifications, before Tax	232	83	17
Other Comprehensive Income (Loss), before Tax	103	66	88
Other Comprehensive Income (Loss), Tax [Abstract]
Other Comprehensive Income (Loss) before Reclassifications, Tax	(57)	(19)	0
Other Comprehensive Income (Loss), Tax	(27)	(15)	(13)
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
OCI, before Reclassifications, Net of Tax	175	64	17
Other comprehensive income (loss)	76	51	75
AOCI before Tax, ending balance	154	51	(15)
AOCI Tax, ending balance	(39)	(12)	3
AOCI, ending balance	115	39	(12)
Accumulated other comprehensive income (loss):
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCI before Tax, beginning balance	(104)	(112)	(140)
AOCI Tax, beginning balance	(10)	6	17
AOCI, beginning balance	(114)	(106)	(123)
Other Comprehensive Income (Loss), before Tax [Abstract]
Other Comprehensive Income (Loss), before Tax	209	8	28
Other Comprehensive Income (Loss), Tax [Abstract]
Other Comprehensive Income (Loss), Tax	(25)	(16)	(11)
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Other comprehensive income (loss)	184	(8)	17
AOCI before Tax, ending balance	105	(104)	(112)
AOCI Tax, ending balance	(35)	(10)	6
AOCI, ending balance	70	(114)	(106)
Cost of revenues | Unrealized gains on cash flow hedges:
Other Comprehensive Income (Loss), before Tax [Abstract]
Reclassification from AOCI, Current Period, before Tax	(109)	(14)	59
Other Comprehensive Income (Loss), Tax [Abstract]
Reclassification from AOCI, Current Period, Tax	26	3	(11)
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Reclassification from AOCI, Current Period, Net of Tax	(83)	(11)	48
Selling, general and administrative expenses | Unrealized gains on cash flow hedges:
Other Comprehensive Income (Loss), before Tax [Abstract]
Reclassification from AOCI, Current Period, before Tax	(20)	(3)	12
Other Comprehensive Income (Loss), Tax [Abstract]
Reclassification from AOCI, Current Period, Tax	4	1	(2)
Other Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Reclassification from AOCI, Current Period, Net of Tax	$ (16)	$ (2)	$ 10

Commitments and Contingencies90

Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Loss Contingencies [Line Items]
Rent expense									$ 265	$ 227	$ 212
Selling, general and administrative expenses	$ 700	$ 674	$ 709	$ 686	$ 730	$ 701	$ 654	$ 646	2,769	2,731	$ 2,509
Insurance Receivable (less than)	1								1
Internal Investigation and Related Matters [Member]
Loss Contingencies [Line Items]
Potential Improper Payments	6								6
Potential Improper Payments Remaining Under Investigation	$ 2								$ 2
Out of period adjustment [Member] | Internal Investigation and Related Matters [Member]
Loss Contingencies [Line Items]
Selling, general and administrative expenses					$ 1	$ 3				$ 4

Commitments and Contingencies91

Commitments and Contingencies (Operating Leases) (Details) $ in Millions	Dec. 31, 2017USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,018	$ 188
2,019	178
2,020	156
2,021	124
2,022	87
Thereafter	210
Total minimum lease payments	$ 943

Commitments and Contingencies92

Commitments and Contingencies (Capital Leases) (Details) $ in Millions	Dec. 31, 2017USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,018	$ 9
2,019	6
2,020	5
2,021	4
2,022	4
Thereafter	23
Total minimum lease payments	51
Interest	(10)
Present value of minimum lease payments	$ 41

Employee Benefits (Narrative) (

Employee Benefits (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
United States and Europe [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan expense	$ 91	$ 76	$ 62
India
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan expense	$ 86	79	71
Employee contribution percentage, maximum	12.00%
Gratuity Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Amount accrued under gratuity plan net of fund assets	$ 114	106
Fund assets	138	103
Pension and Other Postretirement Benefits Cost (Reversal of Cost)	$ 40	$ 41	$ 30

Stock-Based Compensation Plan94

Stock-Based Compensation Plans (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
2017 Incentive Plan [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares authorized	48.8
Shares available for grant	46.1
Stock Options [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period	4 years
Unrecognized stock-based compensation expense	$ 0
Weighted average remaining requisite service period	6 months
Total intrinsic value of options exercised	$ 78	$ 74	$ 59
Restricted Stock Units [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized stock-based compensation expense	$ 282
Weighted average remaining requisite service period	2 years 2 months 12 days
Performance Stock Units [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unrecognized stock-based compensation expense	$ 60
Weighted average remaining requisite service period	1 year 2 months 13 days
Employee Stock [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares authorized	28
Shares available for grant	2.4
Vesting period	3 months
Eligible employees purchase percentage of whole share of fair market value	90.00%
Shares issued	2.8
Fair value of shares issued	$ 26
Non-Employee Directors [Member] | Stock Options [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period	2 years
Minimum [Member] | Stock Options [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Life of share-based payment award	7 years
Minimum [Member] | Restricted Stock Units [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period	1 year
Minimum [Member] | Performance Stock Units [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period	1 year
Maximum [Member] | Stock Options [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Life of share-based payment award	10 years
Maximum [Member] | Restricted Stock Units [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period	4 years
Maximum [Member] | Performance Stock Units [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period	3 years

Stock-Based Compensation Plan95

Stock-Based Compensation Plans (Schedule Of Allocation Of Total Stock-Based Compensation Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 221	$ 217	$ 192
Income tax benefit	101	49	46
Cost of revenues
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	55	53	39
Selling, general and administrative expenses
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 166	$ 164	$ 153

Stock-Based Compensation Plan96

Stock-Based Compensation Plans (Schedule Of Assumptions Used To Calculate The Fair Value Of Option Grants) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Dividend yield	1.00%	0.00%	0.00%
Stock Options [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Weighted average volatility factor	25.90%	28.30%	28.10%
Weighted average expected life (in years)	4 years 4 months 10 days	4 years 5 months 16 days	4 years 3 months 15 days
Weighted average risk-free interest rate	1.90%	1.10%	1.40%
Weighted average grant date fair value	$ 13.06	$ 15.17	$ 16.53
Employee Stock [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Weighted average volatility factor	24.30%	26.50%	25.80%
Weighted average expected life (in years)	3 months	3 months	3 months
Weighted average risk-free interest rate	0.90%	0.40%	0.10%
Weighted average grant date fair value	$ 9.23	$ 8.74	$ 9.04

Stock-Based Compensation Plan97

Stock-Based Compensation Plans (Summary Of The Activity For Stock Options) (Details) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)$ / sharesshares
Number of Options
Number of Options, Outstanding at beginning of year | shares	2.4
Number of Options, Granted | shares	0
Number of Options, Exercised | shares	(1.7)
Number of Options, Cancelled | shares	0
Number of Options, Expired | shares	0
Number of Options, Outstanding at end of period | shares	0.7
Number of Options, Vested and expected to vest at end of year | shares	0.7
Number of Options, Exercisable at end of year | shares	0.7
Weighted Average Exercise Price (in dollars)
Weighted Average Exercise Price, Outstanding at beginning of year | $ / shares	$ 21.08
Weighted Average Exercise Price, Granted | $ / shares	0
Weighted Average Exercise Price, Exercised | $ / shares	19.76
Weighted Average Exercise Price, Cancelled | $ / shares	0
Weighted Average Exercise Price, Expired | $ / shares	0
Weighted Average Exercise Price, Outstanding at end of year | $ / shares	24.88
Weighted Average Exercise Price, Vested and expected to vest at end of year | $ / shares	24.78
Weighted Average Exercise Price, Exercisable at end of year | $ / shares	$ 23.28
Weighted Average Remaining Life, Outstanding at end of year (in years)	1 year 7 months 21 days
Weighted Average Remaining Life, Vested and expected to vest at end of year (in years)	1 year 7 months 17 days
Weighted Average Remaining Life, Exercisable at end of year (in years)	1 year 5 months 16 days
Aggregate Intrinsic Value, Outstanding at end of year | $	$ 29
Aggregate Intrinsic Value, Vested and expected to vest at end of year | $	29
Aggregate Intrinsic Value, Exercisable at end of year | $	$ 29

Stock-Based Compensation Plan98

Stock-Based Compensation Plans (Summary Of The Activity For Performance Stock Units) (Details) - Performance Stock Units [Member] shares in Millions	12 Months Ended
	Dec. 31, 2017$ / sharesshares
Number of Units
Number of Units, Unvested at beginning of period | shares	2.7
Number of Units, Granted | shares	2
Number of Units, Vested | shares	(0.9)
Number of Units, Forfeited | shares	(0.4)
Number of Units, Reduction due to the achievement of lower than maximum performance milestones | shares	(0.7)
Number of Units, Unvested at end of period | shares	2.7
Weighted Average Grant Date Fair Value (in dollars)
Weighted Average Grant Date Fair Value, Unvested at beginning of period | $ / shares	$ 55.24
Weighted Average Grant Date Fair Value, Granted | $ / shares	60.77
Weighted Average Grant Date Fair Value, Vested | $ / shares	55.07
Weighted Average Grant Date Fair Value, Forfeited | $ / shares	56.81
Weighted Average Grant Date Fair Value, Reduction due to the achievement of lower than maximum performance milestones | $ / shares	55.04
Weighted Average Grant Date Fair Value, Unvested at end of period | $ / shares	$ 59.15

Stock-Based Compensation Plan99

Stock-Based Compensation Plans (Summary Of The Activity For Restricted Stock Units) (Details) - Restricted Stock Units [Member] shares in Millions	12 Months Ended
	Dec. 31, 2017$ / sharesshares
Number of Units
Number of Units, Unvested at beginning of period | shares	4.8
Number of Units, Granted | shares	3.6
Number of Units, Vested | shares	(2.5)
Number of Units, Forfeited | shares	(0.7)
Number of Units, Unvested at end of period | shares	5.2
Weighted Average Grant Date Fair Value (in dollars)
Weighted Average Grant Date Fair Value, Unvested at beginning of period | $ / shares	$ 56.45
Weighted Average Grant Date Fair Value, Granted | $ / shares	67.56
Weighted Average Grant Date Fair Value, Vested | $ / shares	56.81
Weighted Average Grant Date Fair Value, Forfeited | $ / shares	57.63
Weighted Average Grant Date Fair Value, Unvested at end of period | $ / shares	$ 63.80

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party Transaction, Purchases from Related Party	$ 4	$ 2

Segment Information (Revenues F

Segment Information (Revenues From External Customers And Segment Operating Profit) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Revenues	$ 3,828	$ 3,766	$ 3,670	$ 3,546	$ 3,462	$ 3,453	$ 3,370	$ 3,202	$ 14,810	$ 13,487	$ 12,416
Income from operations	$ 657	$ 648	$ 606	$ 570	$ 561	$ 583	$ 591	$ 554	2,481	2,289	2,142
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Less: unallocated costs									1,892	1,910	1,956
Operating Segments [Member]
Segment Reporting Information [Line Items]
Income from operations									4,373	4,199	4,098
Operating Segments [Member] | Financial Services
Segment Reporting Information [Line Items]
Revenues									5,636	5,366	5,003
Income from operations									1,636	1,707	1,642
Operating Segments [Member] | Healthcare
Segment Reporting Information [Line Items]
Revenues									4,263	3,871	3,668
Income from operations									1,304	1,153	1,200
Operating Segments [Member] | Products and Resources
Segment Reporting Information [Line Items]
Revenues									3,040	2,660	2,344
Income from operations									868	851	803
Operating Segments [Member] | Communications, Media and Technology
Segment Reporting Information [Line Items]
Revenues									1,871	1,590	1,401
Income from operations									$ 565	$ 488	$ 453

Segment Information (Revenues A

Segment Information (Revenues And Long-Lived Assets By Geographic Area) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Geographic Areas, Revenues
Revenues	$ 3,828	$ 3,766	$ 3,670	$ 3,546	$ 3,462	$ 3,453	$ 3,370	$ 3,202	$ 14,810	$ 13,487	$ 12,416
Geographic Areas, Long-Lived Assets
Long-lived assets	1,324				1,311				1,324	1,311	1,271
North America [Member]
Geographic Areas, Revenues
Revenues									11,450	10,546	9,759
Geographic Areas, Long-Lived Assets
Long-lived assets	360				279				360	279	242
United Kingdom [Member]
Geographic Areas, Revenues
Revenues									1,150	1,176	1,188
Europe, excluding United Kingdom [Member]
Geographic Areas, Revenues
Revenues									1,248	969	820
Europe [Member]
Geographic Areas, Revenues
Revenues									2,398	2,145	2,008
Geographic Areas, Long-Lived Assets
Long-lived assets	63				52				63	52	32
Rest of World [Member]
Geographic Areas, Revenues
Revenues									962	796	649
Geographic Areas, Long-Lived Assets
Long-lived assets	$ 901				$ 980				$ 901	$ 980	$ 997

Quarterly Financial Data (Un103

Quarterly Financial Data (Unaudited) (Summary Of Quarterly Financial Data) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Data [Abstract]
Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount	$ 24	$ 5	$ 5	$ 6					$ 40	$ 24	$ 34
Revenues	3,828	3,766	3,670	3,546	$ 3,462	$ 3,453	$ 3,370	$ 3,202	14,810	13,487	12,416
Cost of revenues (exclusive of depreciation and amortization expense shown separately below)	2,360	2,337	2,261	2,194	2,078	2,077	2,038	1,915	9,152	8,108	7,440
Selling, general and administrative expenses	700	674	709	686	730	701	654	646	2,769	2,731	2,509
Depreciation and amortization expense	111	107	94	96	93	92	87	87	408	359	325
Income from operations	657	648	606	570	561	583	591	554	2,481	2,289	2,142
Net income	$ (18)	$ 495	$ 470	$ 557	$ 416	$ 444	$ 252	$ 441	$ 1,504	$ 1,553	$ 1,624
Basic earnings per share	$ (0.03)	$ 0.84	$ 0.80	$ 0.92	$ 0.69	$ 0.73	$ 0.42	$ 0.73	$ 2.54	$ 2.56	$ 2.67
Diluted earnings per share	(0.03)	0.84	0.80	0.92	$ 0.68	$ 0.73	$ 0.41	$ 0.72	2.53	$ 2.55	$ 2.65
Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Per Share Amount	$ 0.04	$ 0.01	$ 0.01	$ 0.01					$ 0.07

Valuation And Qualifying Acc104

Valuation And Qualifying Accounts (Valuation And Qualifying Accounts) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounts Receivable Allowance For Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 48	$ 39	$ 37
Charged to Costs and Expenses	15	12	10
Charged to Other Accounts	3	0	0
Deductions/Other	1	3	8
Balance at End of Period	65	48	39
Warranty Accrual [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	26	24	21
Charged to Costs and Expenses	30	28	28
Charged to Other Accounts	0	0	0
Deductions/Other	26	26	25
Balance at End of Period	30	26	24
Valuation Allowance - Deferred Income Tax Assets [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	10	10	11
Charged to Costs and Expenses	0	0	3
Charged to Other Accounts	0	0	0
Deductions/Other	0	0	4
Balance at End of Period	$ 10	$ 10	$ 10