CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Common Stock [Member]	Capital in Excess of Par Value [Member]	Reinvested Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Noncontrolling Interest [Member]
Balance at Dec. 31, 2013		$ 10,876	$ 31,729	$ 156,983	$ (9,422)	$ 6,826
Net earnings	$ 19,824	0	0	19,020	0	804
Foreign currency translation adjustments	(2,374)	0	0	0	(1,960)	(414)
Pension liability adjustment, net of tax	6,648	0	0	0	(6,648)	0
Cash dividends declared		0	0	(8,137)	0	0
Cash dividends paid to noncontrolling interest of subsidiary		0	0	0	0	(198)
Stock options exercised		218	4,663	0	0	0
Issuance of restricted stock		24	(24)	0	0	0
Stock-based compensation expense		0	1,465	0	0	0
Income tax benefit from stock options exercised and vesting of restricted stock		0	133	0	0	0
Shares purchased and retired		(297)	0	(7,687)	0	0
Balance at Dec. 31, 2014		10,821	37,966	160,179	(18,030)	7,018
Net earnings	18,153	0	0	18,212	0	(59)
Foreign currency translation adjustments	(3,411)	0	0	0	(2,797)	(614)
Pension liability adjustment, net of tax	(2,360)	0	0	0	2,360	0
Cash dividends declared		0	0	(8,563)	0	0
Stock options exercised		279	5,865	0	0	0
Issuance of restricted stock		22	(22)	0	0	0
Stock-based compensation expense		0	1,559	0	0	0
Income tax benefit from stock options exercised and vesting of restricted stock		0	391	0	0	0
Shares purchased and retired		(355)	0	(9,503)	0	0
Balance at Dec. 31, 2015	204,729	10,767	45,759	160,325	(18,467)	6,345
Net earnings	16,993	0	0	16,472	0	521
Foreign currency translation adjustments	198	0	0	0	202	(4)
Pension liability adjustment, net of tax	(1,696)	0	0	0	1,696	0
Cash dividends declared		0	0	(8,772)	0	0
Cash dividends paid to noncontrolling interest of subsidiary		0	0	0	0	(170)
Stock options exercised		123	2,871	0	0	0
Issuance of restricted stock		27	(27)	0	0	0
Restricted stock forfeited		(2)	2
Stock-based compensation expense		0	1,559	0	0	0
Income tax benefit from stock options exercised and vesting of restricted stock		0	20	0	0	0
Shares purchased and retired		(410)	0	(10,557)	0	0
Balance at Dec. 31, 2016	$ 208,280	$ 10,505	$ 50,184	$ 157,468	$ (16,569)	$ 6,692