Income Taxes - (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Income taxes (benefit)	$ (70)	$ 0	$ (589)	$ 242
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	$ (360)	$ (156)	(1,734)	$ (1,181)
Effective Income Tax Rate Reconciliation, Percent	19.40%
Current Income Taxes Receivable	$ 370		$ 370