Income Taxes - Components of Income Tax (Benefit) Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current
Federal	$ (7)	$ (4)	$ (13)
State	1	2	3
Foreign	37	79	105
Deferred
Federal	23	(88)	19
State	(6)	(7)	(4)
Foreign	7	(30)	(12)
Total income tax expense (benefit)	$ 55	$ (48)	$ 98