Income Taxes (Unaudited) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Consolidated effective income tax rate (percent)			(5.00%)	25.00%
U.S. operations	$ (49)	$ 829	$ (38)	$ 1,664
International operations	(67)	(130)	(155)	(251)
Total	$ (116)	$ 699	(193)	1,413
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount			$ 1,500	$ 763
Effective Income Tax Rate, Adjusted, Percent			33.00%	38.00%