Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands		Total	Revision of Prior Period, Reclassification, Adjustment [Member]	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member] Revision of Prior Period, Reclassification, Adjustment [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Retained Earnings [Member] Revision of Prior Period, Reclassification, Adjustment [Member]
Beginning balance at Dec. 31, 2020		$ 202,506		$ 56	$ (199,796)	$ 363,055		$ 1,611	$ 37,580
Beginning balance (ASU 2020-06) at Dec. 31, 2020			$ (30,267)				$ (30,500)			$ 233
Beginning balance, shares at Dec. 31, 2020				55,633,155	27,510,552
Issuance of common stock from restricted stock awards, shares				24,815
Impact of net settlements		(370)				(370)
Impact of net settlements, shares				290	290
Stock-based compensation expense	[1]	7,425				7,425
Comprehensive income:
Unrealized gain (loss) on foreign currency exchange		1,034						1,034
Net income		1,810							1,810
Ending balance at Mar. 31, 2021		182,138		$ 56	$ (199,796)	339,610		2,645	39,623
Ending balance, shares at Mar. 31, 2021				55,658,260	27,510,842
Beginning balance at Dec. 31, 2020		202,506		$ 56	$ (199,796)	363,055		1,611	37,580
Beginning balance (ASU 2020-06) at Dec. 31, 2020			$ (30,267)				$ (30,500)			$ 233
Beginning balance, shares at Dec. 31, 2020				55,633,155	27,510,552
Comprehensive income:
Net income		6,930
Ending balance at Jun. 30, 2021		193,832		$ 56	$ (199,796)	345,609		3,220	44,743
Ending balance, shares at Jun. 30, 2021				55,669,885	27,510,842
Beginning balance at Mar. 31, 2021		182,138		$ 56	$ (199,796)	339,610		2,645	39,623
Beginning balance, shares at Mar. 31, 2021				55,658,260	27,510,842
Issuance of common stock from exercise of options, shares				2,500
Issuance of common stock from exercise of options		16				16
Issuance of common stock from restricted stock awards, shares				9,125
Registration fees		(29)				(29)
Stock-based compensation expense		6,012				6,012
Comprehensive income:
Unrealized gain (loss) on foreign currency exchange		575						575
Net income		5,120							5,120
Ending balance at Jun. 30, 2021		193,832		$ 56	$ (199,796)	345,609		3,220	44,743
Ending balance, shares at Jun. 30, 2021				55,669,885	27,510,842
Beginning balance at Dec. 31, 2021		222,757		$ 57	$ (199,796)	383,436		298	38,762
Beginning balance, shares at Dec. 31, 2021				57,144,740	27,510,842
Issuance of common stock from restricted stock awards, shares				122,571
Purchase of common stock through stock buyback		(323)			$ (323)
Purchase of common stock through stock buyback, shares					4,614
Impact of net settlements		(4,382)				4,382
Impact of net settlements, shares				1,340	1,340
Stock-based compensation expense	[1]	18,744				18,744
Comprehensive income:
Unrealized gain (loss) on investments		(69)						(69)
Unrealized gain (loss) on foreign currency exchange		(2,695)						(2,695)
Net income		7,164							7,164
Ending balance at Mar. 31, 2022		241,196		$ 57	$ (200,119)	397,798		(2,466)	45,926
Ending balance, shares at Mar. 31, 2022				57,268,651	27,516,796
Beginning balance at Dec. 31, 2021		222,757		$ 57	$ (199,796)	383,436		298	38,762
Beginning balance, shares at Dec. 31, 2021				57,144,740	27,510,842
Comprehensive income:
Unrealized gain (loss) on investments		(207)
Net income		19,579
Ending balance at Jun. 30, 2022		238,402		$ 57	$ (217,288)	406,933		(9,641)	58,341
Ending balance, shares at Jun. 30, 2022				57,276,651	27,769,289
Beginning balance at Mar. 31, 2022		241,196		$ 57	$ (200,119)	397,798		(2,466)	45,926
Beginning balance, shares at Mar. 31, 2022				57,268,651	27,516,796
Issuance of common stock from restricted stock awards, shares				8,000
Purchase of common stock through stock buyback		(17,169)			$ (17,169)
Purchase of common stock through stock buyback, shares					252,493
Stock-based compensation expense	[1]	9,135				9,135
Comprehensive income:
Unrealized gain (loss) on investments		(138)						(138)
Unrealized gain (loss) on foreign currency exchange		(7,037)						(7,037)
Net income		12,415							12,415
Ending balance at Jun. 30, 2022		$ 238,402		$ 57	$ (217,288)	$ 406,933		$ (9,641)	$ 58,341
Ending balance, shares at Jun. 30, 2022				57,276,651	27,769,289

[1] Includes $9.1 and $0.8 million of accrued compensation expense incurred in previous year for the six months ended June 30, 2022 and 2021, respectively.