Income Taxes - Components of Income Before Tax and Benefit for Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Components of income (loss) before income taxes
United States			$ (309)	$ (631)	$ (361)
Foreign			15	(173)	(16)
Net loss from continuing operations before income taxes			(294)	(804)	(377)
Current
U.S. Federal			(58)	6	(47)
U.S. State			1	(1)	(7)
Foreign			10	6	14
Total			(47)	11	(40)
Deferred
U.S. Federal			(222)	(4)	(3)
U.S. State			(46)	(4)	(2)
Foreign			(3)	(6)	(2)
Total	$ 71	$ 181	(271)	(14)	(7)
Total income tax benefit			$ (318)	$ (3)	$ (47)