Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock [Member]	Total
Balance (in shares) at Dec. 31, 2015	19,748,321				1,431,139
Balance at Dec. 31, 2015	$ 197	$ 82,094	$ 8,161	$ (4,049)	$ (8,519)	$ 77,884
Net income			10,590			10,590
Other comprehensive income				(534)		(534)
Cummaltive effect adjustment to retained earnings		165	(93)			72
Issuance of common stock for stock options exercised (in shares)	233,798
Issuance of common stock for stock options exercised	$ 3	1,439				1,442
Vested restricted stock units (in shares)	58,229
Vested restricted stock units
Stock-based compensation expense		1,680				1,680
Repurchase of common stock at cost (in shares)					21,671
Repurchase of common stock at cost					$ (311)	(311)
Common stock cash dividend paid			(3,323)			(3,323)
Balance (in shares) at Dec. 31, 2016	20,040,348				1,452,810
Balance at Dec. 31, 2016	$ 200	85,378	15,335	(4,583)	$ (8,830)	87,500
Net income			17,177			17,177
Other comprehensive income				2,294		2,294
Issuance of common stock for stock options exercised (in shares)	635,503
Issuance of common stock for stock options exercised	$ 7	5,493				5,500
Vested restricted stock units (in shares)	69,190
Vested restricted stock units
Stock-based compensation expense		2,256				2,256
Repurchase of common stock at cost (in shares)					27,291
Repurchase of common stock at cost					$ (778)	(778)
Common stock cash dividend paid			(4,179)			(4,179)
Balance (in shares) at Dec. 31, 2017	20,745,041				1,480,101
Balance at Dec. 31, 2017	$ 207	93,127	28,333	(2,289)	$ (9,608)	109,770
Net income			22,943			22,943
Other comprehensive income				(1,611)		$ (1,611)
Issuance of common stock for stock options exercised (in shares)	303,379					303,379	[1]
Issuance of common stock for stock options exercised	$ 3	2,966				$ 2,969
Vested restricted stock units (in shares)	61,804
Vested restricted stock units
Stock-based compensation expense		2,349				2,349
Repurchase of common stock at cost (in shares)					21,410
Repurchase of common stock at cost					$ (741)	(741)
Common stock cash dividend paid			(5,445)			(5,445)
Balance (in shares) at Dec. 31, 2018	21,110,224				1,501,511
Balance at Dec. 31, 2018	$ 211	$ 98,442	$ 45,831	$ (3,900)	$ (10,349)	$ 130,235

[1] The aggregate intrinsic value of shares exercised represents the difference between the exercise price and the closing price of our stock on the date of exercise.