Fresh Start Accounting - Liabilities Subject to Compromise (Details) $ in Millions	Feb. 09, 2021 USD ($)
Reorganization, Chapter 11 [Line Items]
Liabilities subject to compromise	$ 0
Consideration provided to settle amounts per the Plan or Reorganization:
Issuance of Successor common stock to FLLO Term Loan holders, incremental to the Rights Offering and Backstop Commitment	(783)
Issuance of Successor common stock to Second Lien Note holders, incremental to the Rights Offering and Backstop Commitment	(124)
Issuance of Successor common stock to unsecured note holders	(45)
Issuance of Successor common stock to general unsecured claims	(8)
Class A Warrants
Consideration provided to settle amounts per the Plan or Reorganization:
Warrants	(93)
Class B Warrants
Consideration provided to settle amounts per the Plan or Reorganization:
Warrants	(94)
Class C Warrants
Consideration provided to settle amounts per the Plan or Reorganization:
Warrants	(68)
Predecessor
Reorganization, Chapter 11 [Line Items]
Liabilities subject to compromise	9,574
To be reinstated on the Effective Date:
Accounts payable	(2)
Other current liabilities	(191)
Other long-term liabilities	(2)
Total liabilities reinstated	(195)
Consideration provided to settle amounts per the Plan or Reorganization:
Issuance of Successor common stock associated with the Rights Offering and Backstop Commitment and settlement of the Put Option Premium	(2,311)
Proceeds from issuance of Successor common stock associated with the Rights Offering and Backstop Commitment	600
Issuance of Successor common stock to FLLO Term Loan holders, incremental to the Rights Offering and Backstop Commitment	(783)
Issuance of Successor common stock to Second Lien Note holders, incremental to the Rights Offering and Backstop Commitment	(124)
Issuance of Successor common stock to unsecured note holders	(45)
Issuance of Successor common stock to general unsecured claims	(8)
Proceeds to holders of general unsecured claims	(10)
Total consideration provided to settle amounts per the Plan	(2,936)
Gain on settlement of liabilities subject to compromise	6,443
Predecessor | Class A Warrants
Consideration provided to settle amounts per the Plan or Reorganization:
Warrants	(93)
Predecessor | Class B Warrants
Consideration provided to settle amounts per the Plan or Reorganization:
Warrants	(94)
Predecessor | Class C Warrants
Consideration provided to settle amounts per the Plan or Reorganization:
Warrants	$ (68)