Condensed Consolidated Statement of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Statement of Other Comprehensive Income [Abstract]
Net income	$ 677	$ 570
Other comprehensive income (loss), net of reclassification adjustments:
Foreign currency translation	(301)	218
Unrealized gains (losses) on investments, net	140	217
Tax (expense) benefit on unrealized gains (losses) on investments, net	(54)	(62)
Unrealized gains (losses) on hedging activities, net	86	(59)
Tax (expense) benefit on unrealized gains (losses) on hedging activities, net	(3)	1
Other comprehensive income (loss), net tax	(132)	315
Comprehensive income	$ 545	$ 885