Condensed Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Net revenues	$ 53,494us-gaap_Revenues	$ 48,284us-gaap_Revenues
Cost of net revenues	40,860us-gaap_CostOfRevenue	38,216us-gaap_CostOfRevenue
Gross profit	12,634us-gaap_GrossProfit	10,068us-gaap_GrossProfit
Operating costs and expenses:
Research and development	10,758us-gaap_ResearchAndDevelopmentExpense	8,618us-gaap_ResearchAndDevelopmentExpense
Sales and marketing	4,224us-gaap_SellingAndMarketingExpense	3,995us-gaap_SellingAndMarketingExpense
General and administrative	5,364us-gaap_GeneralAndAdministrativeExpense	5,076us-gaap_GeneralAndAdministrativeExpense
Amortization of purchased intangible assets	167us-gaap_AmortizationOfIntangibleAssets	140us-gaap_AmortizationOfIntangibleAssets
Restructuring charges	(164)us-gaap_RestructuringCharges	1,166us-gaap_RestructuringCharges
Total operating costs and expenses	20,349us-gaap_OperatingExpenses	18,995us-gaap_OperatingExpenses
Operating loss	(7,715)us-gaap_OperatingIncomeLoss	(8,927)us-gaap_OperatingIncomeLoss
Other income (expense):
Interest income (expense), net	(74)	15
Other expense, net	(17)us-gaap_OtherNonoperatingIncomeExpense	(44)us-gaap_OtherNonoperatingIncomeExpense
Loss before income taxes	(7,806)	(8,956)
Income tax provision	20us-gaap_IncomeTaxExpenseBenefit	25us-gaap_IncomeTaxExpenseBenefit
Net loss	$ (7,826)	$ (8,981)
Per share data:
Basic and diluted ($ per share)	$ (0.17)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.26)us-gaap_EarningsPerShareBasicAndDiluted
Weighted average shares used in computation of basic and diluted net loss per share:
Basic and diluted (in shares)	46,262	34,172

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