Fresh Start Accounting - Narrative (Details) - USD ($) $ in Millions		5 Months Ended	12 Months Ended
	May 17, 2023	May 17, 2023	Dec. 31, 2024	Dec. 31, 2023	May 16, 2023
Reorganization, Chapter 11 [Line Items]
Voting shares of successor, percentage	50.00%	50.00%
Total Assets	$ 7,059	$ 7,059	$ 6,106	$ 7,121	$ 7,800
Total Liabilities	4,628	4,628	$ 4,719	$ 4,587	$ 9,800
Enterprise value	$ 4,500	$ 4,500
Nuclear fuel discount rate			8.50%
Shares outstanding (in shares)	59,028,843	59,028,843	45,961,910	59,028,843
Equity-classified warrants	$ 8	$ 8
Cash paid for reorganization expenses		$ 308
Minimum
Reorganization, Chapter 11 [Line Items]
Weighted average cost of capital, discount rate	8.50%	8.50%
Maximum
Reorganization, Chapter 11 [Line Items]
Weighted average cost of capital, discount rate	46.50%	46.50%
Reorganization Adjustments
Reorganization, Chapter 11 [Line Items]
Total Assets	$ (722)	$ (722)
Total Liabilities	(4,138)	$ (4,138)
Payment of professional fees	$ 52