Fresh Start Accounting - Liabilities Subject to Compromise (Details) $ in Thousands	Sep. 18, 2020 USD ($)
Reorganizations [Abstract]
Senior secured second lien notes	$ 1,629,417
Convertible senior notes	234,055
Senior subordinated notes	251,480
Total settled liabilities subject to compromise	2,114,952
Accounts payable and accrued liabilities	101,431
Oil and gas production payable	16,705
Deferred tax liabilities	289,389
Reinstated Liabilities Subject to Compromise	708,554
Liabilities Subject to Compromise	2,823,506
Issuance of New Common Stock to second lien note holders	(1,014,608)
Issuance of New Common Stock to convertible note holders	(53,400)
Issuance of series A warrants to convertible note holders	(15,683)
Issuance of series B warrants to senior subordinated note holders	(6,398)
Reinstatement of liabilities subject to compromise	(708,553)
Gain on settlement of liabilities subject to compromise	$ 1,024,864