Long-Term Debt - Redemption of Senior Notes (Details) - Senior Notes - USD ($)				12 Months Ended
	Feb. 12, 2021	Sep. 11, 2020	Jul. 15, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Gain from extinguishment of debt				$ 16,000,000	$ 27,000,000	$ 5,000,000
5.375% Senior Notes Due 2024
Debt Instrument [Line Items]
Amount of debt redeemed	$ 900,000,000
Stated interest rate	5.375%
5.625% Senior notes due 2023
Debt Instrument [Line Items]
Amount of debt redeemed		$ 140,000,000	$ 360,000,000
Stated interest rate		5.625%	5.625%
5.125% Senior notes due 2023
Debt Instrument [Line Items]
Amount of debt redeemed		$ 700,000,000
Stated interest rate		5.125%
5.375% Senior notes due 2022
Debt Instrument [Line Items]
Amount of debt redeemed			$ 840,000,000
Stated interest rate			5.375%