Income Taxes - Effective Income Tax Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of the U.S. federal statutory tax rate to the actual tax rate is as follows:
Statutory U.S. federal income tax rate	21.00%	21.00%	35.00%
Foreign earnings at rates different than U.S. federal rate	(3.70%)	(1.50%)	(5.70%)
Valuation allowance adjustments	(31.00%)	(16.80%)	(40.80%)
Impact of U.S. Tax Reform	0.00%	(3.10%)	4.30%
Effective Income Tax Rate Reconciliation, Adjustment Permanent Items, Percent	(3.60%)	(2.50%)	(1.00%)
Effective Income Tax Rate Reconciliation, Reduction of UTBs, Percent	6.20%	0.00%	0.00%
Other	1.90%	(1.00%)	1.80%
Effective income tax rate	(9.20%)	(3.90%)	(6.40%)
Tax Cuts and Jobs Act of 2017, Change in tax rate, deferred tax asset, income tax expense (benefit)	$ 36	$ 93
Unrecognized Tax Benefits, Decrease Resulting from Current Period Tax Positions	$ 7