Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Accumulated Deficit [Member]
Beginning Balances at Dec. 31, 2016	$ 556,607	$ 2,607	$ 1,958,731	$ (61)	$ (1,404,670)
Beginning Balance, shares at Dec. 31, 2016		17,372,793
Stock-based compensation	9,301		9,301
Equity issuance costs	(44)		(44)
Issuance of restricted stock		$ 2	(2)
Issuance of restricted stock, shares		10,213
Issuance of common stock upon vesting of equity-based compensation awards, net of shares withheld for income tax withholdings	(2,035)	$ 28	(28)	(2,035)
Issuance of common stock upon vesting of equity-based compensation awards, net of shares withheld for income tax withholdings, shares		133,018
Net income (loss)	8,525				8,525
Ending Balances at Dec. 31, 2017	572,354	$ 2,637	1,967,958	(2,096)	(1,396,145)
Ending Balance, shares at Dec. 31, 2017		17,516,024
Stock-based compensation	7,891		7,891
Equity issuance costs	(344)		(344)
Issuance of restricted stock		$ 2	(2)
Issuance of restricted stock, shares		15,476
Shares of common stock issued in asset acquisition, net of equity issuance costs	90,020	$ 378	89,642
Shares of common stock issued in asset acquisition, net of equity issuance costs, shares		2,521,573
Issuance of common stock upon vesting of equity-based compensation awards, net of shares withheld for income tax withholdings	(1,261)	$ 26	(26)	(1,261)
Issuance of common stock upon vesting of equity-based compensation awards, net of shares withheld for income tax withholdings, shares		115,990
Net income (loss)	18,826				18,826
Ending Balances at Dec. 31, 2018	687,486	$ 3,043	2,065,119	(3,357)	(1,377,319)
Ending Balance, shares at Dec. 31, 2018		20,169,063
Stock-based compensation	8,784		8,784
Equity issuance costs	(30)		(30)
Shares of common stock issued in asset acquisition, net of equity issuance costs	275,759	$ 150	275,609
Shares of common stock issued in asset acquisition, net of equity issuance costs, shares		15,013,520
Issuance of common stock upon vesting of equity-based compensation awards, net of shares withheld for income tax withholdings	(6,675)	$ 23	(6)	(6,692)
Issuance of common stock upon vesting of equity-based compensation awards, net of shares withheld for income tax withholdings, shares		588,351
Reverse split		$ (2,833)	2,833
Net income (loss)	31,762				31,762
Ending Balances at Dec. 31, 2019	$ 997,086	$ 383	$ 2,352,309	$ (10,049)	$ (1,345,557)
Ending Balance, shares at Dec. 31, 2019		35,770,934