Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Revenue	$ 34,670us-gaap_SalesRevenueNet	$ 46,001us-gaap_SalesRevenueNet
Cost of revenue	24,284us-gaap_CostOfGoodsAndServicesSold	28,131us-gaap_CostOfGoodsAndServicesSold
Gross profit	10,386us-gaap_GrossProfit	17,870us-gaap_GrossProfit
Operating expenses:
Selling, general and administrative	11,368	10,939
Research and development	7,918us-gaap_ResearchAndDevelopmentExpense	6,171us-gaap_ResearchAndDevelopmentExpense
Total operating expenses	19,286us-gaap_OperatingExpenses	17,110us-gaap_OperatingExpenses
Income (loss) from operations	(8,900)us-gaap_OperatingIncomeLoss	760us-gaap_OperatingIncomeLoss
Interest expense, net	89	39
Amortization of debt discount and prepaid debt costs	5	5
Income (loss) from operations before income taxes	(8,994)	716
Income tax provision	347us-gaap_IncomeTaxExpenseBenefit	397us-gaap_IncomeTaxExpenseBenefit
Net income (loss)	$ (9,341)us-gaap_NetIncomeLoss	$ 319us-gaap_NetIncomeLoss
Net income (loss) per share:
Basic (in dollars per share)	$ (0.32)us-gaap_EarningsPerShareBasic	$ 0.01us-gaap_EarningsPerShareBasic
Diluted (in dollars per share)	$ (0.32)us-gaap_EarningsPerShareDiluted	$ 0.01us-gaap_EarningsPerShareDiluted
Weighted average common shares outstanding:
Basic (in shares)	29,445	29,047
Diluted (in shares)	29,445	29,216

Amount of noncash expense included in interest expense to allocate debt discount and premium, and the costs to issue debt and obtain financing over the related debt instruments. Alternate captions include noncash interest expense.

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