Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Sales	$ 317,920	$ 292,013	$ 315,249
Cost of sales	210,352	194,486	210,711
Gross profit	107,568	97,527	104,538
Selling, general and administrative expenses	79,950	79,647	81,271
Research & development	14,543	13,514	14,140
Restructuring charges	4,506	661	3,558
Other (income) expense, net	(365)	310	632
Income from operations	8,934	3,395	4,937
Interest expense	417	555	655
Interest income	(166)	(227)	(156)
Income from continuing operations before income taxes	8,683	3,067	4,438
Income taxes	2,837	1,843	1,828
Net income	$ 5,846	$ 1,224	$ 2,610
Basic earnings per share:
Basic (loss) earnings per share (in dollars per share)	$ 0.45	$ 0.10	$ 0.20
Diluted (loss) earnings per share:
Diluted (loss) earnings per share (in dollars per share)	0.45	0.09	0.20
Cash dividends declared per share: (in dollars per share)	$ 0.04	$ 0.08	$ 0.08