Income Taxes - Schedule of Components of Income Tax (Expense) Benefit (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Current:
Federal	$ (15)	$ 3	$ (113)	$ (9)
State	(2)	1	(31)	(4)
Current income taxes	(17)	4	(144)	(13)
Deferred:
Federal	(184)	(55)	47	68
State	(11)	0	(1)	(21)
Deferred income taxes	(195)	(55)	46	48
Deferred income taxes				47
Investment tax credit	0	0	0	1
Income tax benefit (expense)	$ (212)	$ (51)	$ (98)	$ 35