Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue	$ 156,142us-gaap_Revenues	$ 102,664us-gaap_Revenues	$ 91,206us-gaap_Revenues
Cost of revenue	70,488us-gaap_CostOfRevenue	37,095us-gaap_CostOfRevenue	32,684us-gaap_CostOfRevenue
Gross profit	85,654us-gaap_GrossProfit	65,569us-gaap_GrossProfit	58,522us-gaap_GrossProfit
Research and development	70,863us-gaap_ResearchAndDevelopmentExpense	50,516us-gaap_ResearchAndDevelopmentExpense	40,102us-gaap_ResearchAndDevelopmentExpense
Sales and marketing	20,003us-gaap_SellingAndMarketingExpense	15,741us-gaap_SellingAndMarketingExpense	14,052us-gaap_SellingAndMarketingExpense
General and administrative	16,153us-gaap_GeneralAndAdministrativeExpense	11,614us-gaap_GeneralAndAdministrativeExpense	12,300us-gaap_GeneralAndAdministrativeExpense
Total operating expenses	107,019us-gaap_OperatingExpenses	77,871us-gaap_OperatingExpenses	66,454us-gaap_OperatingExpenses
Loss from operations	(21,365)us-gaap_OperatingIncomeLoss	(12,302)us-gaap_OperatingIncomeLoss	(7,932)us-gaap_OperatingIncomeLoss
Interest and other income	495us-gaap_OtherNonoperatingIncomeExpense	876us-gaap_OtherNonoperatingIncomeExpense	914us-gaap_OtherNonoperatingIncomeExpense
Loss before income taxes	(20,870)	(11,426)	(7,018)
Provision for income taxes	1,738us-gaap_IncomeTaxExpenseBenefit	1,752us-gaap_IncomeTaxExpenseBenefit	13,673us-gaap_IncomeTaxExpenseBenefit
Net loss	$ (22,608)us-gaap_NetIncomeLoss	$ (13,178)us-gaap_NetIncomeLoss	$ (20,691)us-gaap_NetIncomeLoss
Earnings per share:
Basic (in Dollars per share)	$ (0.69)us-gaap_EarningsPerShareBasic	$ (0.45)us-gaap_EarningsPerShareBasic	$ (0.73)us-gaap_EarningsPerShareBasic
Diluted (in Dollars per share)	$ (0.69)us-gaap_EarningsPerShareDiluted	$ (0.45)us-gaap_EarningsPerShareDiluted	$ (0.73)us-gaap_EarningsPerShareDiluted
Weighted-average shares used in computing earnings per share:
Basic (in Shares)	32,707,868	29,493,005	28,378,680
Diluted (in Shares)	32,707,868	29,493,005	28,378,680

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