Income Taxes - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Undistributed earnings of foreign subsidiaries	$ 379
AMT credit carryforward	379	$ 379
Operating loss carryforwards	$ 5,900
Operating loss carryforwards, expiration dates	Jan. 01, 2027
Unrecognized tax benefits	$ 32	$ 32	$ 40