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]	Total
Balance (in shares) at Dec. 31, 2018	15,202,387
Balance at Dec. 31, 2018	$ 15	$ 55,859	$ 103,032	$ (7,985)	$ 150,921
Common shares issued upon exercise of options, net (in shares)	62,694
Common shares issued upon exercise of options, net		457	(177)		280
Restricted shares issued, net (in shares)	48,829
Restricted shares issued, net					0
Share-based compensation expense		1,032			1,032
Cash dividends declared			(3,023)		(3,023)
Common stock reacquired and retired (in shares)	(58,216)
Common stock reacquired and retired		(212)	(824)		(1,036)
Net earnings			5,157		5,157
Cash flow hedges, net of taxes				(11)	(11)
Pensions, net of taxes				749	749
Change in currency translation adjustment, net of taxes				21	21
Balance (in shares) at Jun. 30, 2019	15,255,694
Balance at Jun. 30, 2019	$ 15	57,166	104,165	(7,226)	154,120
Tax benefit from vesting of acquisition-related restricted stock		30			30
Balance (in shares) at Mar. 31, 2019	15,229,775
Balance at Mar. 31, 2019	$ 15	56,536	102,945	(7,771)	151,725
Common shares issued upon exercise of options, net (in shares)	18,533
Common shares issued upon exercise of options, net		88	(18)		70
Restricted shares issued, net (in shares)	10,000
Restricted shares issued, net					0
Share-based compensation expense		551			551
Cash dividends declared			(1,508)		(1,508)
Common stock reacquired and retired (in shares)	(2,614)
Common stock reacquired and retired		(9)	(35)		(44)
Net earnings			2,781		2,781
Cash flow hedges, net of taxes				(6)	(6)
Pensions, net of taxes				502	502
Change in currency translation adjustment, net of taxes				49	49
Balance (in shares) at Jun. 30, 2019	15,255,694
Balance at Jun. 30, 2019	$ 15	57,166	104,165	(7,226)	$ 154,120
Balance (in shares) at Dec. 31, 2019	15,227,604				15,227,604
Balance at Dec. 31, 2019	$ 15	57,442	107,581	(7,484)	$ 157,554
Common shares issued upon exercise of options, net (in shares)	9,620				14,000
Common shares issued upon exercise of options, net		50	(17)		$ 33
Restricted shares issued, net (in shares)	38,015
Restricted shares issued, net					0
Share-based compensation expense		1,061			1,061
Cash dividends declared			(1,521)		(1,521)
Common stock reacquired and retired (in shares)	(43,458)
Common stock reacquired and retired		(159)	(341)		(500)
Net earnings			18,541		18,541
Cash flow hedges, net of taxes				(11)	(11)
Pensions, net of taxes				732	732
Change in currency translation adjustment, net of taxes				(1,401)	$ (1,401)
Balance (in shares) at Jun. 30, 2020	15,231,781				15,231,781
Balance at Jun. 30, 2020	$ 15	58,381	124,243	(8,164)	$ 174,475
Tax benefit from vesting of acquisition-related restricted stock		(13)			(13)
Balance (in shares) at Mar. 31, 2020	15,222,161
Balance at Mar. 31, 2020	$ 15	57,669	109,086	(8,380)	158,390
Common shares issued upon exercise of options, net (in shares)	9,620
Common shares issued upon exercise of options, net		50	(17)		33
Share-based compensation expense		662			662
Net earnings			15,174		15,174
Cash flow hedges, net of taxes				(6)	(6)
Pensions, net of taxes				384	384
Change in currency translation adjustment, net of taxes				(162)	$ (162)
Share-based compensation expense (in shares)
Balance (in shares) at Jun. 30, 2020	15,231,781				15,231,781
Balance at Jun. 30, 2020	$ 15	$ 58,381	$ 124,243	$ (8,164)	$ 174,475