Income Taxes - Schedule of Difference between Provision and U.S. Statutory Income Tax Rate (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income (loss) before income taxes, inclusive of equity in loss of affiliate	$ 541	$ (346)	$ 358
Taxes at the U.S. federal statutory income tax rate	114	(121)	125
Effect of foreign operations	103	(19)	(2)
Tax impact of partnership structure	80	171	0
Change in valuation allowances	87	169	28
Tax Cuts and Jobs Act enactment	(107)	(132)	0
Other - net	(19)	(23)	22
Provision for income taxes	$ 258	$ 45	$ 173
Actual income tax rate	47.70%	(13.00%)	48.30%