Income Taxes (Schedule of Income Tax Provision (Benefit)) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
US	$ 28	$ 108	$ 78
International	152	56	83
Total	180	164	161
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
US	54	156	194
International	(33)	(6)	153
Total	21	150	347
Income tax provision (benefit)	$ 201	$ 314	$ 508