Stockholders' Equity (Stock Options Outstanding and Exercisable by Exercise Price) (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Jul. 16, 2014
Stock Options Outstanding And Exercisable By Exercise Price Range [Line Items]
Number of stock options outstanding	15,634,317
Number of stock options exercisable	8,615,711
Weighted average remaining contractual life of outstanding stock options (years)	4 years 7 months 2 days
Intrinsic value of stock options outstanding	$ 369
Weighted average remaining contractual life of exercisable stock options (years)	3 years 7 months 6 days
Intrinsic value of stock options exercisable	$ 260
Share price	$ 55.34us-gaap_SharePrice	$ 60.85us-gaap_SharePrice
$5 to $9.99 [Member]
Stock Options Outstanding And Exercisable By Exercise Price Range [Line Items]
Exercise price range, lower range limit	$ 5
Exercise price range, upper range limit	$ 9.99
Number of stock options outstanding	757,967
Number of stock options exercisable	757,967
Stock options outstanding, weighted average exercise price	$ 5.26
Stock options exercisable, weighted average exercise price	$ 5.26
Weighted average remaining contractual life of outstanding stock options (years)	2 years 2 months 23 days
$10 to $19.99 [Member]
Stock Options Outstanding And Exercisable By Exercise Price Range [Line Items]
Exercise price range, lower range limit	$ 10
Exercise price range, upper range limit	$ 19.99
Number of stock options outstanding	604,593
Number of stock options exercisable	604,593
Stock options outstanding, weighted average exercise price	$ 14.09
Stock options exercisable, weighted average exercise price	$ 14.09
Weighted average remaining contractual life of outstanding stock options (years)	3 years 4 months 10 days
$20 to $29.99 [Member]
Stock Options Outstanding And Exercisable By Exercise Price Range [Line Items]
Exercise price range, lower range limit	$ 20
Exercise price range, upper range limit	$ 29.99
Number of stock options outstanding	8,417,067
Number of stock options exercisable	5,690,194
Stock options outstanding, weighted average exercise price	$ 25.81
Stock options exercisable, weighted average exercise price	$ 25.68
Weighted average remaining contractual life of outstanding stock options (years)	3 years 8 months 12 days
$30 to $39.99 [Member]
Stock Options Outstanding And Exercisable By Exercise Price Range [Line Items]
Exercise price range, lower range limit	$ 30
Exercise price range, upper range limit	$ 39.99
Number of stock options outstanding	1,426,662
Number of stock options exercisable	1,083,333
Stock options outstanding, weighted average exercise price	$ 34.05
Stock options exercisable, weighted average exercise price	$ 33.92
Weighted average remaining contractual life of outstanding stock options (years)	5 years 4 months 24 days
$40 to $49.99 [Member]
Stock Options Outstanding And Exercisable By Exercise Price Range [Line Items]
Exercise price range, lower range limit	$ 40
Exercise price range, upper range limit	$ 49.99
Number of stock options outstanding	2,400,080
Number of stock options exercisable	477,893
Stock options outstanding, weighted average exercise price	$ 44.14
Stock options exercisable, weighted average exercise price	$ 44.38
Weighted average remaining contractual life of outstanding stock options (years)	6 years 1 month 28 days
$50 to $59.99 [Member]
Stock Options Outstanding And Exercisable By Exercise Price Range [Line Items]
Exercise price range, lower range limit	$ 50
Exercise price range, upper range limit	$ 59.99
Number of stock options outstanding	9,521
Number of stock options exercisable	1,731
Stock options outstanding, weighted average exercise price	$ 59.94
Stock options exercisable, weighted average exercise price	$ 59.94
Weighted average remaining contractual life of outstanding stock options (years)	6 years 9 months 26 days
$60 to $69.99 [Member]
Stock Options Outstanding And Exercisable By Exercise Price Range [Line Items]
Exercise price range, lower range limit	$ 60
Exercise price range, upper range limit	$ 69.99
Number of stock options outstanding	2,018,427
Number of stock options exercisable	0
Stock options outstanding, weighted average exercise price	$ 65.91
Stock options exercisable, weighted average exercise price	$ 0.00
Weighted average remaining contractual life of outstanding stock options (years)	7 years 1 month 17 days

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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-Publisher FASB

-Name Accounting Standards Codification

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Price of a single share of a number of saleable stocks of a company.

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