Condensed Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Treasury [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Treasury Stock, Shares			(790,000)
Common stock, shares, outstanding at Dec. 31, 2018		79,004,000
Beginning Balance, value at Dec. 31, 2018	$ 165,058	$ 7,900	$ (4,965)	$ 550,548	$ (388,425)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	(15,115)				(15,115)
Purchase of treasury stock, shares			(84,000)
Purchase of treasury stock, value	(120)		$ (120)
Equity awards vested or exercised, shares		326,000
Equity awards vested or exercised, value		$ 33		(33)
Stock-based compensation expense	867			867
Common stock, shares, outstanding at Mar. 31, 2019		79,330,000
Ending Balance, value at Mar. 31, 2019	150,967	$ 7,933	(5,085)	551,382	(403,263)
Common stock, shares, outstanding at Dec. 31, 2018		79,004,000
Beginning Balance, value at Dec. 31, 2018	165,058	$ 7,900	(4,965)	550,548	(388,425)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	(54,075)
Common stock, shares, outstanding at Sep. 30, 2019		80,078,000
Ending Balance, value at Sep. 30, 2019	113,148	$ 8,008	$ (5,090)	552,453	(442,223)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Treasury Stock, Shares			(874,000)
Cumulative-effect adjustment due to adoption of ASC Topic 842 | Accounting Standards Update 2016-02 [Member]	277				277
Common stock, shares, outstanding at Mar. 31, 2019		79,330,000
Beginning Balance, value at Mar. 31, 2019	150,967	$ 7,933	$ (5,085)	551,382	(403,263)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	(12,944)				(12,944)
Purchase of treasury stock, shares			(3,000)
Purchase of treasury stock, value	(5)		$ (5)
Equity awards vested or exercised, shares		667,000
Equity awards vested or exercised, value		$ 67		(67)
Stock-based compensation expense	327			327
Common stock, shares, outstanding at Jun. 30, 2019		79,997,000
Ending Balance, value at Jun. 30, 2019	138,345	$ 8,000	$ (5,090)	551,642	(416,207)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Treasury Stock, Shares			(877,000)
Net income (loss)	(26,016)				(26,016)
Equity awards vested or exercised, shares		81,000
Equity awards vested or exercised, value		$ 8		(8)
Stock-based compensation expense	819			819
Common stock, shares, outstanding at Sep. 30, 2019		80,078,000
Ending Balance, value at Sep. 30, 2019	113,148	$ 8,008	$ (5,090)	552,453	(442,223)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Treasury Stock, Shares			(877,000)
Treasury Stock, Shares			(877,000)
Common stock, shares, outstanding at Dec. 31, 2019		80,079,000
Beginning Balance, value at Dec. 31, 2019	104,076	$ 8,008	$ (5,090)	553,210	(452,052)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	(69,104)				(69,104)
Purchase of treasury stock, shares			(165,000)
Purchase of treasury stock, value	(7)		$ (7)
Equity awards vested or exercised, shares		542,000
Equity awards vested or exercised, value		$ 54		(54)
Stock-based compensation expense	328			328
Common stock, shares, outstanding at Mar. 31, 2020		80,621,000
Ending Balance, value at Mar. 31, 2020	35,293	$ 8,062	(5,097)	553,484	(521,156)
Common stock, shares, outstanding at Dec. 31, 2019		80,079,000
Beginning Balance, value at Dec. 31, 2019	104,076	$ 8,008	(5,090)	553,210	(452,052)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	(104,225)
Common stock, shares, outstanding at May. 31, 2020		0
Ending Balance, value at May. 31, 2020	0	$ 0	$ 0	0	0
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Treasury Stock, Shares			(1,042,000)
Common stock, shares, outstanding at Mar. 31, 2020		80,621,000
Beginning Balance, value at Mar. 31, 2020	35,293	$ 8,062	$ (5,097)	553,484	(521,156)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	(35,121)				(35,121)
Purchase of treasury stock, shares			(100,000)
Purchase of treasury stock, value	(1)		$ (1)
Equity awards vested or exercised, shares		363,000
Equity awards vested or exercised, value		$ 36		(36)
Equity awards vested in connection with the Plan, shares		7,946,000
Equity awards vested in connection with the Plan, value		$ 795		(795)
Stock-based compensation expense	978			978
Common stock, shares, outstanding at May. 31, 2020		0
Ending Balance, value at May. 31, 2020	0	$ 0	$ 0	0	0
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Treasury Stock, Shares			0
Issuance of Successor common stock to Prepetition Senior notes creditors and prior equity holders				18,083
Net income (loss)	(9,817)				(9,817)
Purchase of treasury stock, shares			(1,000)
Common stock, shares, outstanding at Jun. 30, 2020		1,050,000
Ending Balance, value at Jun. 30, 2020	129,142	$ 1	$ 0	138,958	(9,817)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Stock Issued During Period, Shares, New Issues		1,050,000
Stock Issued During Period, Value, New Issues	18,084	$ 1
Equity component of Convertible Notes, net of offering costs	120,875			120,875
Common stock, shares, outstanding at May. 31, 2020		0
Beginning Balance, value at May. 31, 2020	0	$ 0	0	0	0
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	$ (29,887)
Common stock, shares, outstanding at Sep. 30, 2020	1,138,185	1,140,000
Ending Balance, value at Sep. 30, 2020	$ 110,045	$ 1	$ 0	139,931	(29,887)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Treasury Stock, Shares			(1,000)
Common stock, shares, outstanding at Jun. 30, 2020		1,050,000
Beginning Balance, value at Jun. 30, 2020	129,142	$ 1	$ 0	138,958	(9,817)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Net income (loss)	(20,070)				(20,070)
Equity awards vested or exercised, shares		90,000
Stock-based compensation expense	$ 973			973
Common stock, shares, outstanding at Sep. 30, 2020	1,138,185	1,140,000
Ending Balance, value at Sep. 30, 2020	$ 110,045	$ 1	$ 0	$ 139,931	$ (29,887)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Treasury Stock, Shares			(1,000)