Fresh Start Accounting - Change in Successor Additional Paid-in Capital (Details) - USD ($) $ in Millions	Feb. 09, 2021	Dec. 31, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Issuance of Successor equity associated with the Rights Offering and Backstop Commitment	$ 2,371
Issuance of Successor equity to holders of the FLLO Term Loan, incremental to the Rights Offering and Backstop Commitment	783
Issuance of Successor equity to holders of the Second Lien Notes, incremental to the Rights Offering and Backstop Commitment	124
Issuance of Successor equity to holders of the unsecured senior notes	45
Issuance of Successor equity to holders of allowed general unsecured claims	8
Total change in Successor common stock and additional paid-in capital	3,586
Less: par value of Successor common stock	(1)	$ (1)	$ (1)
Change in Successor additional paid-in capital	3,585
Class A Warrants
Class of Stock [Line Items]
Warrants	93
Class B Warrants
Class of Stock [Line Items]
Warrants	94
Class C Warrants
Class of Stock [Line Items]
Warrants	$ 68