Fresh Start Accounting (Schedule of Reorganization Items) (Details) - USD ($) $ in Thousands	2 Months Ended	4 Months Ended	8 Months Ended	12 Months Ended
Aug. 31, 2020	Dec. 31, 2020	Aug. 31, 2020	Dec. 31, 2019
Reorganizations [Abstract]
Gains on settlement of liabilities subject to compromise	$ (567,853)	$ 0	$ (567,853)
Fresh start accounting adjustments		0	401,406
Legal and professional fees and expenses		2,273	15,745
Acceleration of Predecessor stock compensation expense		0	1,431
Exit Facility fees		0	3,225
5% equity facility	$ 9,900	0	9,866
Adjustment to unamortized debt issuance costs associated with the 6.625% senior subordinated notes due 2021		0	2,205
Total reorganization items, net		$ 2,273	$ (133,975)	$ 0

Amount of reorganization items related to debtor-in-possession facility financing costs.

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Amount of reorganization items related to employee related charges.

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