Consolidated Statements of Earnings - Unaudited - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Net sales	$ 117,625	$ 113,530
Cost of goods sold	77,010	75,097
Gross Margin	40,615	38,433
Selling, general and administrative expenses	17,522	17,372
Research and development expenses	6,791	6,507
Restructuring charges	2,084	1,195
Operating earnings	14,218	13,359
Other income (expense):
Interest expense	(466)	(541)
Interest income	432	482
Other income, net	96	2,004
Total other income (expense), net	62	1,945
Earnings before income taxes	14,280	15,304
Income tax expense	2,861	3,756
Net earnings	$ 11,419	$ 11,548
Earnings per share:
Basic (in dollars per share)	$ 0.35	$ 0.35
Diluted (in dollars per share)	$ 0.34	$ 0.34
Basic weighted - average common shares outstanding (in shares):	32,807	32,975
Effect of dilutive securities (in shares)	463	540
Diluted weighted - average common shares outstanding (in shares)	33,270	33,515
Cash dividends declared per share (in dollars per share)	$ 0.04	$ 0.04