Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	1 Months Ended	2 Months Ended	3 Months Ended					4 Months Ended	5 Months Ended	9 Months Ended
	Jun. 30, 2023	May 17, 2023	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Mar. 31, 2023	Sep. 30, 2023	May 17, 2023	Sep. 30, 2024
Numerator: (Millions of Dollars)
Net Income (Loss)	$ 31	$ 419	$ 168	$ 458	$ 319	$ (76)	$ 46	$ (45)	$ 465	$ 945
Less:
Net income (loss) attributable to noncontrolling interest			0			1		3	(14)	29
Net Income (Loss) Attributable to Stockholders (Successor) / Member (Predecessor)			$ 168			$ (77)		$ (48)	$ 479	$ 916
Denominator: (Thousands)
Weighted-average shares outstanding - Basic (in shares)			50,924			59,029		59,029	0	55,703
Weighted-average shares outstanding - Diluted (in shares)			53,169			59,029		59,029	0	57,756
Earnings per Share - Basic (in dollars per share)			$ 3.30			$ (1.30)		$ (0.81)		$ 16.44
Earnings per Share - Diluted (in dollars per share)			$ 3.16			$ (1.30)		$ (0.81)		$ 15.86
Restricted stock units
Denominator: (Thousands)
Stock units (in shares)			376			0		0	0	292
Performance stock units
Denominator: (Thousands)
Stock units (in shares)			1,869			0		0	0	1,761