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, 2019	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)	118,788
Common shares issued upon exercise of options, net		1,590	(183)		1,407
Share-based compensation expense		1,790			1,790
Tax withheld on exercise of Stock Appreciation Rights (SARS)		(32)			(32)
Cash dividends declared			(4,574)		(4,574)
Net income			28,485		28,485
Cash flow hedges, net of taxes				(16)	(16)
Pensions, net of taxes				1,026	1,026
Change in currency translation adjustment, net of taxes				(1,546)	(1,546)
Restricted shares issued (in shares)	38,015
Restricted shares issued					0
Tax benefit from vesting of acquisition-related restricted stock		(13)			(13)
Common stock reacquired and retired (in shares)	(43,458)
Common stock reacquired and retired		(159)	(341)		(500)
Balance (in shares) at Sep. 30, 2020	15,340,949
Balance at Sep. 30, 2020	$ 15	60,618	130,968	(8,020)	183,581
Balance (in shares) at Jun. 30, 2020	15,231,781
Balance at Jun. 30, 2020	$ 15	58,381	124,243	(8,164)	174,475
Common shares issued upon exercise of options, net (in shares)	109,168
Common shares issued upon exercise of options, net		1,540	(166)		1,374
Share-based compensation expense		729			729
Tax withheld on exercise of Stock Appreciation Rights (SARS)		(32)			(32)
Cash dividends declared			(3,053)		(3,053)
Net income			9,944		9,944
Cash flow hedges, net of taxes				(5)	(5)
Pensions, net of taxes				294	294
Change in currency translation adjustment, net of taxes				(145)	(145)
Balance (in shares) at Sep. 30, 2020	15,340,949
Balance at Sep. 30, 2020	$ 15	60,618	130,968	(8,020)	$ 183,581
Balance (in shares) at Dec. 31, 2020	15,391,660				15,391,660
Balance at Dec. 31, 2020	$ 15	61,844	141,972	(12,201)	$ 191,630
Common shares issued upon exercise of options, net (in shares)	261,604				262,960
Common shares issued upon exercise of options, net	$ 1	2,629	(178)		$ 2,452
Share-based compensation expense		2,757			2,757
Tax withheld on exercise of Stock Appreciation Rights (SARS)		(405)			(405)
Cash dividends declared			(5,334)		(5,334)
Net income			25,051		25,051
Cash flow hedges, net of taxes				(16)	(16)
Pensions, net of taxes				6,613	6,613
Change in currency translation adjustment, net of taxes				(184)	(184)
Restricted shares issued (in shares)	264,166
Restricted shares issued					0
Tax benefit from vesting of acquisition-related restricted stock		171			171
Performance based shares issued (in shares)	42,823
Performance based shares issued					$ 0
Balance (in shares) at Sep. 30, 2021	15,960,253				15,960,253
Balance at Sep. 30, 2021	$ 16	66,996	161,511	(5,788)	$ 222,735
Balance (in shares) at Jun. 30, 2021	15,824,530
Balance at Jun. 30, 2021	$ 16	65,578	155,212	(5,491)	215,315
Share-based compensation expense		1,088			1,088
Cash dividends declared			(1,897)		(1,897)
Net income			8,196		8,196
Cash flow hedges, net of taxes				(5)	(5)
Pensions, net of taxes				278	278
Change in currency translation adjustment, net of taxes				(570)	(570)
Common shares issued upon exercise of options and SARs, net (in shares)	31,446
Common shares issued upon exercise of options and SARs, net		330			330
Restricted shares issued (in shares)	104,277
Restricted shares issued					$ 0
Balance (in shares) at Sep. 30, 2021	15,960,253				15,960,253
Balance at Sep. 30, 2021	$ 16	$ 66,996	$ 161,511	$ (5,788)	$ 222,735