Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

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).

+ References

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- Definition

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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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Publisher FASB
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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

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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No definition available.

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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Compensation
Stock-based compensation expense		$ 65	$ 58	$ 173	$ 166
Options, grants in period (in shares)				4
Options, grants in period, weighted average grant date fair value (in dollars per share)				$ 9.43
Options, grants in period, weighted average exercise price (in dollars per share)				$ 78.05
Options, outstanding (in shares)	21	21		21
Options, outstanding, weighted average exercise price (in dollars per share)	$ 75.09	$ 75.09		$ 75.09
Options, outstanding, weighted average remaining contractual term (in years)	3 years 10 months 13 days
Employee Stock Option
Compensation
Stock-based compensation expense		$ 15	20	$ 49	60
Restricted Stock Units (RSUs)
Compensation
Stock-based compensation expense		$ 50	$ 38	$ 124	$ 106
Equity instruments other than options, grants in period (in shares)				3
Equity instruments other than options, grants in period, weighted average grant date fair value (in dollars per share)				$ 78.35
Equity instruments other than options, nonvested (in shares)	6	6		6
Equity instruments other than options, nonvested, weighted average grant date fair value (in dollars per share)	$ 87.20	$ 87.20		$ 87.20