Components of Interest and Other Income, net (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Component of Other Income, Nonoperating [Line Items]
Interest income	$ 812	$ 579	$ 230
Interest expense	(58)	(5)	0
Realized gains on available-for-sale investments, net	254	185	97
Impairment of equity investments	(110)	0	0
Foreign currency exchange losses, net	(379)	(355)	(260)
Other	65	11	2
Interest and other income, net	$ 584	$ 415	$ 69