Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Net Sales	$ 212,055	$ 194,909
Operating Earnings, Excluding Indirect Operating Expenses	43,435	40,923
Reconciliation from Segment Totals to Consolidated [Abstract]
Combination-related expenses	(5,209)	(9,075)
Indirect Operating Expenses	(16,142)	(16,317)
Amortization	(1,853)	(1,773)
Operating income	20,231	13,758
Other (expense) income, net	(369)	(105)
Interest Expense	(1,692)	(656)
Interest Income	489	523
Income Before Taxes and Equity in Net Income of Associated Companies	18,659	13,520
North America [Member]
Segment Reporting Information [Line Items]
Net Sales	91,820	87,341
Operating Earnings, Excluding Indirect Operating Expenses	20,365	20,637
North America [Member] | Intersegment Sales Elimination [Member]
Segment Reporting Information [Line Items]
Net Sales	3,100	2,100
EMEA [Member]
Segment Reporting Information [Line Items]
Net Sales	62,055	53,927
Operating Earnings, Excluding Indirect Operating Expenses	10,293	9,246
EMEA [Member] | Intersegment Sales Elimination [Member]
Segment Reporting Information [Line Items]
Net Sales	5,600	4,800
Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net Sales	48,777	45,150
Operating Earnings, Excluding Indirect Operating Expenses	12,142	10,243
Asia Pacific [Member] | Intersegment Sales Elimination [Member]
Segment Reporting Information [Line Items]
Net Sales	400	100
South America [Member]
Segment Reporting Information [Line Items]
Net Sales	9,403	8,491
Operating Earnings, Excluding Indirect Operating Expenses	635	797
South America [Member] | Intersegment Sales Elimination [Member]
Segment Reporting Information [Line Items]
Net Sales	$ 0	$ 100