Income Taxes (Analysis of the Provision for Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
United States	$ 223	$ 350	$ 292
State	56	48	99
Other countries	394	387	286
Total	673	785	677
United States	(180)	67	85
State	(74)	(16)	14
Other countries	(1)	20	52
Total	(255)	71	151
Total provision for income taxes	$ 418	$ 856	$ 828