Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Treasury Stock	Accumulated Deficit	Preferred Stock Series A	Preferred Stock Series A Preferred Stock	Preferred Stock Series A Common Stock	Preferred Stock Series A Additional Paid-In Capital	Preferred Stock Series B	Preferred Stock Series B Preferred Stock	Preferred Stock Series B Common Stock
Beginning Balance (in shares) at Dec. 31, 2019		96,189,074					2,093,155				618
Beginning Balance at Dec. 31, 2019	$ 69,764	$ 96	$ 436,306	$ (47)	$ (366,593)		$ 2				$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,520		1,520
Stock option exercises (in shares)		107,287
Stock option exercises	338		338
Restricted stock awards (in shares)		459,670
Preferred stock conversion to common stock (in shares)							(2,093,155)	2,093,155			(175)	972,222
Preferred stock conversion to common stock						$ (1)	$ (2)	$ 2	$ (1)	$ 1		$ 1
Net income	4,966				4,966
Ending Balance (in shares) at Mar. 31, 2020		99,821,408					0				443
Ending Balance at Mar. 31, 2020	76,588	$ 99	438,163	(47)	(361,627)		$ 0				$ 0
Beginning Balance (in shares) at Dec. 31, 2019		96,189,074					2,093,155				618
Beginning Balance at Dec. 31, 2019	69,764	$ 96	436,306	(47)	(366,593)		$ 2				$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	15,515
Ending Balance (in shares) at Sep. 30, 2020		101,126,452					0				443
Ending Balance at Sep. 30, 2020	95,885	$ 100	446,910	(47)	(351,078)		$ 0				$ 0
Beginning Balance (in shares) at Mar. 31, 2020		99,821,408					0				443
Beginning Balance at Mar. 31, 2020	76,588	$ 99	438,163	(47)	(361,627)		$ 0				$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	4,786		4,786
Stock option exercises (in shares)		983,437
Stock option exercises	2,231		2,231
Restricted stock awards (in shares)		111,666
Net income	1,165				1,165
Ending Balance (in shares) at Jun. 30, 2020		100,916,511					0				443
Ending Balance at Jun. 30, 2020	84,770	$ 99	445,180	(47)	(360,462)		$ 0				$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,539		1,539
Stock option exercises (in shares)		68,623
Stock option exercises	192	$ 1	191
Restricted stock awards (in shares)		141,318
Net income	9,384				9,384
Ending Balance (in shares) at Sep. 30, 2020		101,126,452					0				443
Ending Balance at Sep. 30, 2020	95,885	$ 100	446,910	(47)	(351,078)		$ 0				$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,750		1,750
Stock option exercises (in shares)		240,656
Stock option exercises	609	$ 1	608
Restricted stock awards (in shares)		50,333
Restricted stock awards	(1)	$ 3	(4)
Share repurchase	(205)			(205)
Net income	10,196				10,196
Ending Balance (in shares) at Dec. 31, 2020		101,417,441					0				443
Ending Balance at Dec. 31, 2020	108,234	$ 104	449,264	(252)	(340,882)		$ 0				$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,490		1,490
Stock option exercises (in shares)		16,619
Stock option exercises	40		40
Restricted stock awards (in shares)		268,174
Share repurchase	(6,147)			(6,147)
Net income	5,237				5,237
Ending Balance (in shares) at Mar. 31, 2021		101,702,234					0				443
Ending Balance at Mar. 31, 2021	108,854	$ 104	450,794	(6,399)	(335,645)		$ 0				$ 0
Beginning Balance (in shares) at Dec. 31, 2020		101,417,441					0				443
Beginning Balance at Dec. 31, 2020	$ 108,234	$ 104	449,264	(252)	(340,882)		$ 0				$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock option exercises (in shares)	155,690
Net income	$ 20,970
Ending Balance (in shares) at Sep. 30, 2021		102,057,290					0				443
Ending Balance at Sep. 30, 2021	122,775	$ 104	454,738	(12,155)	(319,912)		$ 0				$ 0
Beginning Balance (in shares) at Mar. 31, 2021		101,702,234					0				443
Beginning Balance at Mar. 31, 2021	108,854	$ 104	450,794	(6,399)	(335,645)		$ 0				$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,697		1,697
Stock option exercises (in shares)		25,828
Stock option exercises	59		59
Restricted stock awards (in shares)		66,668
Share repurchase	(5,756)			(5,756)
Net income	9,064				9,064
Ending Balance (in shares) at Jun. 30, 2021		101,794,730					0				443
Ending Balance at Jun. 30, 2021	113,918	$ 104	452,550	(12,155)	(326,581)		$ 0				$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,837		1,837
Stock option exercises (in shares)		113,243
Stock option exercises	351		351
Restricted stock awards (in shares)		149,317
Net income	6,669				6,669
Ending Balance (in shares) at Sep. 30, 2021		102,057,290					0				443
Ending Balance at Sep. 30, 2021	$ 122,775	$ 104	$ 454,738	$ (12,155)	$ (319,912)		$ 0				$ 0