Income Taxes - Narrative (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2021
Operating Loss Carryforwards [Line Items]
Net discrete tax benefits	$ 4			$ (7)
True up adjustment to prior year tax provision	5			5
Tax expense related to equity compensation vesting	1			4
Discrete tax expense related to an uncertain tax position	2			3
Income tax expense (benefit)	2	$ (9)		36	$ (151)
Pre-tax income (loss)	$ 19	$ (10)		$ 150	$ (27)
Effective tax rate (percentage)	10.50%	90.00%		24.00%	559.30%
True-ups of forecasted marginal rate expense (benefit)				$ (1)
Discrete income tax expense (benefit)		$ (9)	$ (152)		$ (122)
Income tax expense (benefit), marginal tax rate adjustment					$ 29
Scenario, Forecast
Operating Loss Carryforwards [Line Items]
Effective tax rate (percentage)						27.00%