Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Capital in Excess of Par Value [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (loss) [Member]
Balance at Dec. 31, 2018	$ 64,228	$ 270	$ 116,427	$ 82,548	$ (120,406)	$ (14,611)
Balance, shares at Dec. 31, 2018		27,018,000			12,746,000
Employee Stock Purchase Plan share issuance	147		(152)		$ 299
Employee Stock Purchase Plan share issuance, shares					(32,000)
Stock Option Plan share issuance, net	$ 91		(663)		$ 754
Stock Option Plan share issuance, shares	(80,000)				(45,000)
Restricted stock plan share issuance/forfeiture	$ (172)		(3,230)		$ 3,058
Restricted stock plan share issuance/forfeiture, shares					143,000
Deferred compensation plan share issuance			(2,034)		$ 2,034
Deferred compensation plan share issuance, shares					(215,000)
Equity-based compensation	1,748		1,748
Net income	4,125			4,125
Foreign currency translation adjustment	(1,084)					(1,084)
Pension loss adjustment, net of tax	(2,847)					(2,847)
Balance at Dec. 31, 2019	66,236	$ 270	112,096	86,673	$ (114,261)	(18,542)
Balance, shares at Dec. 31, 2019		27,018,000			12,311,000
Employee Stock Purchase Plan share issuance	$ 143		(128)		$ 271
Employee Stock Purchase Plan share issuance, shares					(29,000)
Stock Option Plan share issuance, net			(193)		$ 193
Stock Option Plan share issuance, shares	0				(6,000)
Restricted stock plan share issuance/forfeiture	$ (168)		(4,851)		$ 4,683
Restricted stock plan share issuance/forfeiture, shares					(434,000)
Equity-based compensation	2,483		2,483
Net income	7,639			7,639
Foreign currency translation adjustment	5,461					5,461
Pension loss adjustment, net of tax	(2,286)					(2,286)
Balance at Dec. 31, 2020	$ 79,508	$ 270	109,407	94,312	$ (109,114)	(15,367)
Balance, shares at Dec. 31, 2020	27,017,824	27,018,000			11,842,000
Employee Stock Purchase Plan share issuance	$ 165		(9)		$ 174
Employee Stock Purchase Plan share issuance, shares					(19,000)
Stock Option Plan share issuance, net	$ 366		(427)		$ 793
Stock Option Plan share issuance, shares	(65,300)				(82,000)
Restricted stock plan share issuance/forfeiture	$ (399)		(1,281)		$ 882
Restricted stock plan share issuance/forfeiture, shares					73,000
Equity-based compensation	2,640		2,640
Net income	13,730			13,730
Foreign currency translation adjustment	(4,052)					(4,052)
Pension loss adjustment, net of tax	2,479					2,479
Balance at Dec. 31, 2021	$ 94,437	$ 270	$ 110,330	$ 108,042	$ (107,265)	$ (16,940)
Balance, shares at Dec. 31, 2021	27,017,824	27,018,000			11,668,000