Income Taxes - Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current Income Taxes
Federal	$ 3	$ (6)	$ 7
State	16	8	113
Total current income taxes	19	2	120
Deferred Income Taxes
Federal	110	245	376
State	25	44	(25)
Total deferred income taxes	135	289	351
Total income tax expense	$ 154	$ 291	$ 471