Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Stock Appreciation Rights (SARs) [Member] Common Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balance (in shares) at Dec. 31, 2016		14,513,207
Balance at Dec. 31, 2016		$ 15	$ 42,416	$ 74,283	$ (6,164)	$ 110,550
Common shares issued upon exercise of options (in shares)		285,745
Common shares issued upon exercise of options			2,779	(907)		1,872
Restricted shares issued (in shares)		181,399
Restricted shares issued			2,780			2,780
Common shares issued upon exercise of Stock Appreciation Rights (SARs) (in shares)	101,596
Share-based compensation expense			1,664			1,664
Tax withheld on exercise of Stock Appreciation Rights (SARs)			(1,186)			(1,186)
Tax benefit from vesting of acquisition related restricted stock			650			650
Cash dividends declared				(5,269)		(5,269)
Net income				15,022		15,022
Cash flow hedges, net of taxes					(111)	(111)
Pensions, net of taxes					(1,024)	(1,024)
Change in currency translation adjustment, net of taxes					20	20
Cash flow hedges, net of taxes						(111)
Balance (in shares) at Dec. 31, 2017		15,081,947
Balance at Dec. 31, 2017		$ 15	49,103	83,129	(7,279)	124,968
Common shares issued upon exercise of options (in shares)		87,347
Common shares issued upon exercise of options			878	(151)		727
Restricted shares issued (in shares)		150,094
Restricted shares issued			3,762			3,762
Common shares issued upon exercise of Stock Appreciation Rights (SARs) (in shares)	3,428	37,930
Share-based compensation expense			2,264			2,264
Tax withheld on exercise of Stock Appreciation Rights (SARs)			(17)			(17)
Tax benefit from vesting of acquisition related restricted stock			445			445
Cash dividends declared				(5,836)		(5,836)
Net income				16,975		16,975
Cash flow hedges, net of taxes					203	203
Pensions, net of taxes					(391)	(391)
Change in currency translation adjustment, net of taxes					(518)	(518)
ASC 606 adjustment to opening retained earnings				11,245		$ 11,245
Common shares reacquired and retired (in shares)		(158,359)				(58,216)
Common shares reacquired and retired			(576)	(2,330)		$ (2,906)
Cash flow hedges, net of taxes						$ 203
Balance (in shares) at Dec. 31, 2018		15,202,387				15,202,387
Balance at Dec. 31, 2018		$ 15	55,859	103,032	(7,985)	$ 150,921
Common shares issued upon exercise of options (in shares)						75,444
Common shares issued upon exercise of options			460	(177)		$ 283
Restricted shares issued (in shares)		69,530
Restricted shares issued
Common shares issued upon exercise of Stock Appreciation Rights (SARs) (in shares)		62,994
Share-based compensation expense			1,484			1,484
Tax benefit from vesting of acquisition related restricted stock			30			30
Cash dividends declared				(6,046)		(6,046)
Net income				12,066		12,066
Change in currency translation adjustment, net of taxes					74	$ 74
Common shares reacquired and retired (in shares)		(107,307)				(49,091)
Common shares reacquired and retired			(391)	(1,294)		$ (1,685)
Cash flow hedges, net of taxes					(22)	(22)
Pensions, net of taxes					449	$ 449
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