Income Taxes (Income Tax Expense (Benefit)) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Expense (Benefit) [Abstract]
United States	$ 5	$ 2	$ (45)
Other nations	89	30	183
States (U.S.)	1	3	74
Current income tax expense	95	35	212
United States	296	(118)	373
Other nations	(12)	111	(54)
States (U.S.)	(42)	(31)	(128)
Deferred income tax expense (benefit)	242	(38)	191
Total income tax expense (benefit)	$ 337	$ (3)	$ 403