Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Sales	$ 79,882	$ 64,557
Cost of sales	51,744	43,388
Gross profit	28,138	21,169
Selling, general and administrative expenses	20,361	17,574
Research & development	3,281	3,559
Restructuring	1,352	1,436
Other operating expense, net	509	155
Income (loss) from operations	2,635	(1,555)
Other non-operating (income) expense, net	(99)	230
Interest expense	49	105
Interest income	(51)	(40)
Income (loss) before income taxes	2,736	(1,850)
Income tax expense	917	198
Net Income (loss)	$ 1,819	$ (2,048)
Per share data:
Basic earnings (loss) per share (in dollars per share)	$ 0.14	$ (0.16)
Diluted earnings (loss) per share (in dollars per share)	0.14	(0.16)
Cash dividends declared per share (in dollars per share)	$ 0	$ 0.02