Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Net Sales	$ 190,428	$ 189,224	$ 555,420	$ 554,280
Operating Earnings, Excluding Indirect Operating Expenses	41,036	40,510	118,897	116,620
Reconciliation from Segment Totals to Consolidated [Abstract]
Indirect Operating Expenses	(17,967)	(20,031)	(50,912)	(53,585)
Amortization	(1,730)	(1,751)	(5,319)	(4,998)
Operating income	21,339	18,728	62,666	58,037
Other income (expense), net	514	185	1,491	(97)
Interest Expense	(758)	(697)	(2,226)	(1,891)
Interest Income	551	422	1,444	1,117
Income Before Taxes and Equity in Net Income of Associated Companies	21,646	18,638	63,375	57,166
North America [Member]
Segment Reporting Information [Line Items]
Net Sales	86,126	90,010	251,586	258,977
Operating Earnings, Excluding Indirect Operating Expenses	20,324	21,893	59,078	59,938
North America [Member] | Intersegment Sales Elimination [Member]
Segment Reporting Information [Line Items]
Net Sales	2,500	2,300	6,300	6,900
EMEA [Member]
Segment Reporting Information [Line Items]
Net Sales	49,825	45,989	150,582	130,345
Operating Earnings, Excluding Indirect Operating Expenses	8,295	7,106	25,251	20,538
EMEA [Member] | Intersegment Sales Elimination [Member]
Segment Reporting Information [Line Items]
Net Sales	5,300	5,200	13,200	14,600
Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net Sales	45,892	46,067	130,555	138,913
Operating Earnings, Excluding Indirect Operating Expenses	11,737	11,250	33,865	33,874
Asia Pacific [Member] | Intersegment Sales Elimination [Member]
Segment Reporting Information [Line Items]
Net Sales	100	300	500	500
South America [Member]
Segment Reporting Information [Line Items]
Net Sales	8,585	7,158	22,697	26,045
Operating Earnings, Excluding Indirect Operating Expenses	680	261	703	2,270
South America [Member] | Intersegment Sales Elimination [Member]
Segment Reporting Information [Line Items]
Net Sales	$ 0	$ 0	$ 100	$ 100