Condensed Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock [Member]	Total
Balances at Dec. 31, 2019	$ 30	$ 162,154	$ (93,357)	$ (2,209)	$ (33,726)	$ 32,892
Purchase of shares of treasury stock					(4,425)	(4,425)
Issuance of common shares for the exercise of stock options		3,145				3,145
Non-cash stock compensation expense		332				332
Other comprehensive income, foreign currency translation adjustment				(1,124)		(1,124)
Net income			11,755			11,755
Dividends declared of $0.21 per common share			(5,278)			(5,278)
Balances at Mar. 31, 2020	30	165,631	(86,880)	(3,333)	(38,151)	37,297
Balances at Dec. 31, 2020	31	171,785	(61,375)	(2,399)	(43,727)	64,315
Purchase of shares of treasury stock					(1,210)	(1,210)
Issuance of common shares for the exercise of stock options		911				911
Non-cash stock compensation expense		(54)				(54)
Other comprehensive income, foreign currency translation adjustment				56		56
Net income			9,232			9,232
Balances at Mar. 31, 2021	$ 31	$ 172,642	$ (52,143)	$ (2,343)	$ (44,937)	$ 73,250