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]
Revenue	$ 167,372	$ 186,586	$ 193,534
Cost of revenue	116,410	118,143	118,244
Gross profit	50,962	68,443	75,290
Operating expenses:
Selling, general and administrative	40,758	43,022	43,543
Research and development	24,697	26,320	22,542
Restructuring and exit costs	2,512	0	0
Total operating expenses	67,967	69,342	66,085
Income (loss) from operations	(17,005)	(899)	9,205
Interest expense, net	266	169	4
Amortization of prepaid debt costs	18	20	60
Foreign currency exchange loss, net	441	838	649
Income (loss) before income taxes	(17,730)	(1,926)	8,492
Income tax provision	4,603	4,346	2,152
Net income (loss)	$ (22,333)	$ (6,272)	$ 6,340
Net income (loss) per share:
Basic (in dollars per share)	$ (0.73)	$ (0.21)	$ 0.22
Diluted (in dollars per share)	$ (0.73)	$ (0.21)	$ 0.22
Weighted average common shares outstanding:
Basic (in shares)	30,716	29,216	28,869
Diluted (in shares)	30,716	29,216	28,903