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 loss	(15,115)				(15,115)
Purchase of treasury stock, shares			(84,000)
Purchase of treasury stock, value	(120)		$ (120)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification | Accounting Standards Update 2016-02 [Member]	277				277
Issuance of restricted stock, shares		326,000
Issuance of restricted stock, 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)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Treasury Stock, Shares			(874,000)
Treasury Stock, Shares			(877,000)
Common stock, shares, outstanding at Dec. 31, 2019	79,202,216	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 loss	(69,104)				(69,104)
Purchase of treasury stock, shares			(165,000)
Purchase of treasury stock, value	(7)		$ (7)
Issuance of restricted stock, shares		542,000
Issuance of restricted stock, value		$ 54		(54)
Stock-based compensation expense	$ 328			328
Common stock, shares, outstanding at Mar. 31, 2020	79,579,571	80,621,000
Ending Balance, value at Mar. 31, 2020	$ 35,293	$ 8,062	$ (5,097)	$ 553,484	$ (521,156)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Treasury Stock, Shares			(1,042,000)