Income Taxes - Narrative (Details) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2020 USD ($) Installment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2017 USD ($)
Income Taxes [Line Items]
Income tax (benefit) expense				$ 110	$ 474	$ 303
Income (loss) before income taxes				(1,140)	177	1,011
Net discrete tax adjustments			$ 135	305	386	65
Discrete adjustments, net charge				10
Valuation allowance	$ 1,469			1,469	982
Deferred tax impact of enacted tax rate and law changes				(18)	3	0
Discrete adjustments, other	8					18
Federal and state tax on accelerated royalty income transaction				0	334	0
Increase in valuation allowance on tax losses in subsidiaries					150
Reduction to valuation allowance for foreign tax credits					98
Net deferred tax assets	1,879			1,879	1,979
Deferred tax asset, tax credit carryforwards, foreign	133			133	403
Deferred tax assets	3,348			3,348	2,961
Deferred tax assets, operating loss, capital loss, and tax credit carryforwards	704			704
Operating loss carryforwards, domestic	767			767
Operating loss carryforwards, state and local	99			99
Unrecognized tax benefits	85		71	85	82	71		$ 52
Unrecognized tax benefits that would impact effective tax rate	58			58
Income tax penalties and interest accrued	2			2
Unsettled unrecognized tax benefits that would require cash	9			9
Undistributed earnings of foreign subsidiaries	2,300			2,300
Amount of unrecognized deferred tax liability, undistributed earnings of foreign subsidiaries	85			$ 85
CARES act of 2020, net operating loss carryback period				5 years
CARES Act Of 2020 refundable alternative minimum tax credit carryforwards		$ 5
Number of equal annual installments to receive refund alternative minimum tax credit carryforwards | Installment				2
Income tax cash payments, net				$ 45	142	178
Foreign Tax Authority
Income Taxes [Line Items]
Tax credit carryforward, valuation allowance	328			328	3		$ 295
Valuation allowance	1,101			1,101	1,000
Net establishment (release) of U.S. valuation allowances				$ 0	140	(5)
Tax credit carryforward expiration period				through 2024 and a portion of those expiring in 2025.
Increase in valuation allowance				$ 30
Deferred tax assets	1,300			1,300	1,200
Deferred tax assets, operating loss, capital loss, and tax credit carryforwards, subject to expiration	69			$ 69
Foreign Tax Authority | Beginning Year
Income Taxes [Line Items]
Tax credit carryforward expiration year				2025
Foreign Tax Authority | Ending Year
Income Taxes [Line Items]
Tax credit carryforward expiration year				2030
Domestic Tax Authority
Income Taxes [Line Items]
Valuation allowance	15			$ 15
Net establishment (release) of U.S. valuation allowances				310	(98)	25
Deferred tax asset, tax credit carryforwards, foreign	461			461
Tax credit carryforwards, research	92			92
Venezuela
Income Taxes [Line Items]
Tax credit carryforward, valuation allowance			98			$ 98
Net establishment (release) of U.S. valuation allowances			$ (88)
Domestic and State and Local Authority
Income Taxes [Line Items]
Valuation allowance	368			368	13
Net deferred tax assets	1,200			1,200	$ 1,200
Net deferred tax assets, unlimited lives	900			900
Net deferred tax assets, limited lives	300			$ 300
Net deferred tax assets, expiration period				between 2025 and 2040.
State and Local Authority
Income Taxes [Line Items]
Operating loss carryforwards, subject to expiration	87			$ 87
England
Income Taxes [Line Items]
Deferred tax impact of enacted tax rate and law changes		$ (13)
Luxembourg | Foreign Tax Authority
Income Taxes [Line Items]
Valuation allowance	$ 978			$ 978