Income Taxes - Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Current Income Taxes
Federal	$ 7	$ (3)	$ 19
State	113	92	74
Total current income taxes	120	89	93
Deferred Income Taxes
Federal	376	87	(303)
State	(25)	(83)	(68)
Total deferred income taxes	351	4	(371)
Total income tax expense (benefit)	$ 471	$ 93	$ (278)