Provision for Income Taxes (Schedule of Current and Deferred income Tax Expense) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Tax Disclosure [Abstract]
Current U.S. federal tax expense (benefit)	$ 397	$ (109)	$ 23
Current U.S. state and local tax expense (benefit)	(11)	0	(9)
Current international tax expense (benefit)	586	454	328
Total current tax expense	972	345	342
Deferred U.S. federal tax expense (benefit)	(144)	245	57
Deferred U.S. state and local tax expense (benefit)	(4)	3	1
Deferred international tax expense (benefit)	(52)	66	15
Total deferred tax (benefit) expense	(200)	314	73
Provision for income taxes	$ 772	$ 659	$ 415