Unaudited Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Revenue	$ 73,679	$ 87,942	$ 218,287	$ 257,346
Cost of revenue	48,313	56,715	144,071	170,340
Gross profit	25,366	31,227	74,216	87,006
Expenses:
Selling, general and administrative	24,424	23,634	71,859	70,223
Depreciation and amortization	2,706	2,785	7,896	8,258
Research and development	2,531	2,031	7,059	5,273
Impairment of inventory and long-lived assets	0	0	40,435	20,372
Total expenses	29,661	28,450	127,249	104,126
(Loss) income from operations	(4,295)	2,777	(53,033)	(17,120)
Other (expense) income:
Interest expense	(611)	(476)	(1,811)	(1,303)
Other (expense) income, net	(49)	74	(207)	(154)
Total other expense	(660)	(402)	(2,018)	(1,457)
(Loss) income before income taxes	(4,955)	2,375	(55,051)	(18,577)
Income tax benefit (expense)	2,209	(400)	19,840	6,490
Net (loss) income	$ (2,746)	$ 1,975	$ (35,211)	$ (12,087)
(Loss) earnings per common share:
Basic (loss) earnings per common share (in dollars per share)	$ (0.05)	$ 0.04	$ (0.63)	$ (0.22)
Diluted (loss) earnings per common share (in dollars per share)	$ (0.05)	$ 0.04	$ (0.63)	$ (0.22)
Weighted average common shares:
Weighted average common shares used in computing basic (loss) earnings per common share (in shares)	56,899	54,578	55,523	54,430
Weighted average common shares used in computing diluted (loss) earnings per common share (in shares)	56,899	54,947	55,523	54,430