Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Common Stock Outstanding [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2016	21,273,500
Balance at Dec. 31, 2016	$ 21	$ 212,103	$ (39,507)	$ (497)	$ 39,431	$ 211,551
Net income					17,028	17,028
Other comprehensive income (loss)				(89)		(89)
Equity-based compensation		8,693				8,693
Issuance of treasury stock upon exercise of stock-based awards (in shares)	790,507
Issuance of treasury stock upon exercise of stock-based awards	$ 1	(3,379)	13,451		(2,586)	$ 7,487
Purchase of treasury stock (in shares)						0
Balance (in shares) at Dec. 31, 2017	22,064,007
Balance at Dec. 31, 2017	$ 22	217,417	(26,056)	(586)	53,873	$ 244,670
Net income					574	574
Other comprehensive income (loss)				(528)		(528)
Equity-based compensation		10,367				10,367
Issuance of treasury stock upon exercise of stock-based awards (in shares)	379,729
Issuance of treasury stock upon exercise of stock-based awards		(4,534)	6,932		(149)	$ 2,249
Purchase of treasury stock (in shares)	(655,876)					(655,876)
Purchase of treasury stock			(20,008)			$ (20,008)
Cumulative effect of adoption of new accounting standard (Note 2)					8,555	8,555
Balance (in shares) at Dec. 31, 2018	21,787,860
Balance at Dec. 31, 2018	$ 22	223,250	(39,132)	(1,114)	62,853	245,879
Accumulated other comprehensive income, net as of December 31, 2019						(1,114)
Net income					28	28
Other comprehensive income (loss)				1,208		1,208
Equity-based compensation		10,718				10,718
Issuance of treasury stock upon exercise of stock-based awards (in shares)	406,689
Issuance of treasury stock upon exercise of stock-based awards		(5,963)	8,855		(455)	$ 2,437
Purchase of treasury stock (in shares)	(355,180)					(355,180)
Purchase of treasury stock			(9,113)			$ (9,113)
Balance (in shares) at Dec. 31, 2019	21,839,369
Balance at Dec. 31, 2019	$ 22	$ 228,005	$ (39,390)	94	$ 62,426	251,157
Accumulated unrealized gain from available-for-sale securities, net of taxes of $5				45
Accumulated unrealized gain from hedging activities, net of taxes of $7				49
Accumulated other comprehensive income, net as of December 31, 2019				$ 94		$ 94