Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income
Balance at Dec. 31, 2016	$ (24,440)		$ 364	$ 596,067	$ (621,804)	$ 933
Balance, shares at Dec. 31, 2016			36,391,129
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(426,899)				(426,899)
Other comprehensive income, net of tax	10					10
Reclassification adjustment related to adoption of accounting guidance					(114)	114
Share-based compensation	2,212			2,212
Share-based compensation issuances, net, shares			982,487
Share-based compensation issuances, net	(76)		$ 10	(86)
Balance at Dec. 31, 2017	$ (449,193)		$ 374	598,193	(1,048,817)	1,057
Balance, shares at Dec. 31, 2017	0
Balance, shares at Dec. 31, 2017	37,373,616		37,373,616
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 521,007				521,007
Other comprehensive income, net of tax	0
Share-based compensation	538			538
Fresh start and reorganization adjustments, shares		100,000	(33,121,116)
Fresh start and reorganization adjustments	152,706	$ 1	$ (331)	(414,387)	568,480	(1,057)
Balance at Feb. 09, 2018	184,388	$ 1	$ 43	184,344	0	0
Balance, shares at Feb. 09, 2018		100,000
Balance, shares at Feb. 09, 2018			4,252,500
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(205,094)				(205,094)
Other comprehensive income, net of tax	92					92
Share-based compensation	2,491			2,491
Share-based compensation issuances, net, shares			88,070
Conversion of preferred stock to common stock, shares		(8,592)	987,847
Conversion of preferred stock to common stock	0		$ 10	(10)
Balance at Dec. 31, 2018	$ (18,123)	$ 1	$ 53	$ 186,825	$ (205,094)	$ 92
Balance, shares at Dec. 31, 2018	91,408	91,408
Balance, shares at Dec. 31, 2018	5,328,417		5,328,417