Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Additional Paid-in Capital	Treasury Stock	Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss Cumulative Effect, Period of Adoption, Adjustment	Accumulated (Deficit)
Beginning balance (in shares) at Dec. 31, 2020			59,590,422
Beginning balance, treasury stock (in shares) at Dec. 31, 2020					(26,678,410)
Beginning balance at Dec. 31, 2020	$ 196,775	$ (4,445)	$ 596	$ 1,059,624	$ (468,613)	$ 0	$ (4,445)	$ (394,832)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)			239,275
Exercise of stock options	(1,070)		$ 2	(1,072)
Exercise of stock warrants (in shares)			561,900
Exercise of stock warrants	13,686		$ 6	13,680
Stock compensation expense	3,892			3,892
Net income	60,865							60,865
Ending balance, treasury stock (in shares) at Jun. 30, 2021					(26,678,410)
Ending balance (in shares) at Jun. 30, 2021			60,391,597
Ending balance at Jun. 30, 2021	269,703		$ 604	1,076,124	$ (468,613)	(4,445)		(333,967)
Beginning balance (in shares) at Mar. 31, 2021			59,806,077
Beginning balance, treasury stock (in shares) at Mar. 31, 2021					(26,678,410)
Beginning balance at Mar. 31, 2021	229,196	(1,478)	$ 598	1,058,504	$ (468,613)	(2,967)	(1,478)	(358,326)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)			23,731
Exercise of stock options	2,024			2,024
Exercise of stock warrants (in shares)			561,789
Exercise of stock warrants	13,681		$ 6	13,675
Stock compensation expense	1,921			1,921
Net income	24,359							24,359
Ending balance, treasury stock (in shares) at Jun. 30, 2021					(26,678,410)
Ending balance (in shares) at Jun. 30, 2021			60,391,597
Ending balance at Jun. 30, 2021	$ 269,703		$ 604	1,076,124	$ (468,613)	(4,445)		(333,967)
Beginning balance (in shares) at Dec. 31, 2021	34,145,311		60,830,853
Beginning balance, treasury stock (in shares) at Dec. 31, 2021	(26,685,542)				(26,685,542)
Beginning balance at Dec. 31, 2021	$ 314,715	(4,691)	$ 608	1,084,288	$ (468,879)	(8,047)	(4,691)	(293,255)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)			290,205
Exercise of stock options	4,339		$ 3	4,336
Stock compensation expense	5,738			5,738
Net income	$ 91,513							91,513
Ending balance, treasury stock (in shares) at Jun. 30, 2022	(26,685,542)				(26,685,542)
Ending balance (in shares) at Jun. 30, 2022	34,435,516		61,121,058
Ending balance at Jun. 30, 2022	$ 411,614		$ 611	1,094,362	$ (468,879)	(12,738)		(201,742)
Beginning balance (in shares) at Mar. 31, 2022			60,913,663
Beginning balance, treasury stock (in shares) at Mar. 31, 2022					(26,685,542)
Beginning balance at Mar. 31, 2022	356,441	$ (10,139)	$ 609	1,087,054	$ (468,879)	(2,599)	$ (10,139)	(259,744)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)			207,395
Exercise of stock options	3,500		$ 2	3,498
Stock compensation expense	3,810			3,810
Net income	$ 58,002							58,002
Ending balance, treasury stock (in shares) at Jun. 30, 2022	(26,685,542)				(26,685,542)
Ending balance (in shares) at Jun. 30, 2022	34,435,516		61,121,058
Ending balance at Jun. 30, 2022	$ 411,614		$ 611	$ 1,094,362	$ (468,879)	$ (12,738)		$ (201,742)