Stock Incentive Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Compensation
Recognized tax benefit on compensation expense	$ 22	$ 26	$ 33
Excess tax benefits from stock-based compensation	72	127	106
Proceeds from exercise of stock options	224	299	421
Total intrinsic value of options exercised	244	394	372
Restricted Stock
Compensation
Total fair value of restricted shares vested	$ 218	$ 164	$ 57
Restricted Stock Units (RSUs)
Compensation
Granted (in shares)	1,992,000	2,695,000	2,708,000
Granted (in dollars per share)	$ 103.26	$ 100.81	$ 73.60
Unrecognized compensation expense related to unvested options	$ 327
Unrecognized compensation expense related to unvested options, period of recognition (in years)	2 years 3 months 15 days
Options Granted, Beginning from 2011
Compensation
Exercisable period (in years)	4 years
Expiration period for options granted (in years)	7 years
Employee Stock Option
Compensation
Unrecognized compensation expense related to unvested options	$ 79
Unrecognized compensation expense related to unvested options, period of recognition (in years)	1 year 9 months 16 days
Fair value of options vested	$ 298	$ 334	$ 292
Unvested options to vest over the requisite service period (in shares)	$ 11
Employee Stock Purchase Plan 2007
Compensation
Maximum number of shares that can be purchased under ESPP (in shares)	30,000,000
Employee purchase price, percentage of fair market value of ordinary shares	90.00%	85.00%
Shares of common stock purchased for ESPP (in shares)	1,000,000
Average price of shares of common stock purchased for ESPP (in dollars per share)	$ 84.68
Shares available for future grants under the ICP (in shares)	12,000,000
Equity Incentive Plan 2010
Compensation
Maximum number of shares that can be purchased under ESPP (in shares)	74,000,000
Shares available for future grants under the ICP (in shares)	18,000,000
Minimum
Compensation
Requisite service period of the stock award (in years)	3 years
Maximum
Compensation
Requisite service period of the stock award (in years)	5 years

Represents period of expiration of equity based awards.

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Share-based compensation arrangement by share-based payment award, unvested stock expected to vest.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

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The number of shares purchased on the open market during the period for issuance to employees under the plan.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Purchase price of common stock expressed as a percentage of its fair value.

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