Income Taxes (Analysis of the Provision for Income Taxes) (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	$ 182	$ 43	$ 368
State	30	32	95
Other countries	332	311	337
Total	544	386	800
United States	204	254	(15)
State	34	29	(24)
Other countries	(14)	(9)	27
Total	224	274	(12)
Total provision for income taxes	$ 768	$ 660	$ 788