Consolidated Statements of Stockholders' Equity (USD $) In Millions, unless otherwise specified	Total	Common Stock	Paid-in Capital	Retained Earnings	Treasury Common Stock	AOCI
Balance at Dec. 31, 2011		$ 1,741	$ 1,194	$ 26,278	$ (17,485)	$ (776)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,759us-gaap_NetIncomeLoss	0	0	1,759	0	0
Dividends declared and paid		0	0	(819)	0	0
Common stock issued for stock-based awards		0	(337)	0	823	0
Stock repurchases		0	0	0	(1,800)	0
Stock-based compensation		0	263	0	0	0
Tax impact from exercise of options	133	0	56	0	0	0
Other comprehensive income (loss), net of taxes	77	0	0	0	0	77
Dividend equivalents paid on restricted stock units		0	0	(13)	0	0
Balance at Dec. 31, 2012		1,741	1,176	27,205	(18,462)	(699)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,162us-gaap_NetIncomeLoss	0	0	2,162	0	0
Dividends declared and paid		0	0	(1,175)	0	0
Common stock issued for stock-based awards		0	(273)	0	1,540	0
Stock repurchases		0	0	0	(2,868)	0
Stock-based compensation		0	287	0	0	0
Tax impact from exercise of options	227	0	25	0	0	0
Other comprehensive income (loss), net of taxes	171	0	0	0	0	171
Dividend equivalents paid on restricted stock units		0	0	(19)	0	0
Other		0	(4)	0	0	0
Balance at Dec. 31, 2013		1,741	1,211	28,173	(19,790)	(528)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,821us-gaap_NetIncomeLoss	0	0	2,821	0	0
Dividends declared and paid		0	0	(1,323)	0	0
Common stock issued for stock-based awards		0	(226)	0	781	0
Stock repurchases		0	0	0	(2,831)	0
Stock-based compensation		0	277	0	0	0
Tax impact from exercise of options	218	0	110	0	0	0
Other comprehensive income (loss), net of taxes	(4)	0	0	0	0	(4)
Dividend equivalents paid on restricted stock units		0	0	(18)	0	0
Other		0	(4)	0	0	0
Balance at Dec. 31, 2014		$ 1,741	$ 1,368	$ 29,653	$ (21,840)	$ (532)

This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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