Fresh Start Accounting (Schedule of Reorganization Items) (Details) - USD ($) $ in Thousands		1 Months Ended	2 Months Ended	3 Months Ended	8 Months Ended	9 Months Ended
	Aug. 31, 2020	Sep. 30, 2020	Aug. 31, 2020	Sep. 30, 2019	Aug. 31, 2020	Sep. 30, 2019
Reorganizations [Abstract]
Gains on settlement of liabilities subject to compromise		$ 0	$ (567,853)		$ (567,853)
Fresh start accounting adjustments		0	401,406		401,406
Legal and professional fees and expenses		1,155	10,923		15,745
Acceleration of Predecessor stock compensation expense	$ 1,400	0	1,431		1,431
Exit Facility fees		0	3,225		3,225
5% equity facility		0	9,866		9,866
Adjustment to unamortized debt issuance costs associated with the 6.625% senior subordinated notes due 2021		0	0		2,205
Total reorganization items, net		$ 1,155	$ (141,002)	$ 0	$ (133,975)	$ 0