Income Taxes - Reconciliation of Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Line Items]
U.S. federal income tax expense (benefit) at the statutory rate of 21%	$ (239)	$ 37	$ 212
Net foreign losses (income) with no tax due to valuation allowances	37	48	7
Goodwill impairment	34	0	0
Deferred tax impact of enacted tax rate and law changes	(18)	3	0
State income taxes, net of U.S. federal benefit	(17)	(1)	(1)
U.S. charges (benefits) related to foreign tax credits, R&D and foreign derived intangible deduction	(9)	(17)	20
Adjustment for foreign income taxed at different rates	7	16	30
Net establishment of uncertain tax positions	6	7	18
Federal and state tax on accelerated royalty income transaction	0	334	0
Other	(1)	5	(3)
United States and Foreign Tax Expense	110	474	303
Foreign Tax Authority
Income Taxes [Line Items]
Net establishment (release) of U.S. valuation allowances	0	140	(5)
Domestic Tax Authority
Income Taxes [Line Items]
Net establishment (release) of U.S. valuation allowances	$ 310	$ (98)	$ 25