Provision for Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Income Tax Disclosure [Abstract]
Provision for (benefit from) income taxes on continuing operations	$ (134)	$ 75	$ 657	$ 616
Income (loss) from continuing operations	(174)	451	3,131	3,478
Tax expense (benefit) primarily associated with the company's policy of hedging the foreign currency-denominated monetary assets and liabilities	$ (71)	$ 42	$ (48)	$ (101)