Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Net revenue	$ 172,532	$ 178,404	$ 119,434
Cost of goods sold	107,785	119,587	82,028
Gross margin	64,747	58,817	37,406
Operating expenses:
Research, development and engineering	18,831	19,426	16,915
Selling, general and administrative	31,870	28,866	27,842
Restructuring and other charges	2,526	412	3,662
Total operating expenses	53,227	48,704	48,419
Income (loss) from operations	11,520	10,113	(11,013)
Interest income (expense), net	(135)	(228)	(494)
Other income (expense), net	(208)	335	(10)
Income (loss) before income taxes	11,177	10,220	(11,517)
Provision for (benefit from) income taxes	862	339	(542)
Net income (loss)	$ 10,315	$ 9,881	$ (10,975)
Net income (loss) per share:
Basic (in usd per share)	$ 0.14	$ 0.14	$ (0.19)
Diluted (in usd per share)	$ 0.13	$ 0.13	$ (0.19)
Shares used in computing net income (loss) per share:
Basic (in shares)	74,916	71,897	58,944
Diluted (in shares)	76,815	73,403	58,944