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
Revenue	$ 73,538us-gaap_SalesRevenueNet	$ 60,061us-gaap_SalesRevenueNet
Cost of revenue	33,855us-gaap_CostOfRevenue	27,964us-gaap_CostOfRevenue
Gross profit	39,683us-gaap_GrossProfit	32,097us-gaap_GrossProfit
Operating expenses:
Research and development	16,038	15,603
Selling, general and administrative	17,518	16,109
Litigation expense (benefit), net	270us-gaap_LitigationSettlementAmount	(8,700)us-gaap_LitigationSettlementAmount
Total operating expenses	33,826us-gaap_OperatingExpenses	23,012us-gaap_OperatingExpenses
Income from operations	5,857us-gaap_OperatingIncomeLoss	9,085us-gaap_OperatingIncomeLoss
Interest and other income, net	642us-gaap_OtherNonoperatingIncomeExpense	190us-gaap_OtherNonoperatingIncomeExpense
Income before income taxes	6,499	9,275
Income tax provision	536us-gaap_IncomeTaxExpenseBenefit	257us-gaap_IncomeTaxExpenseBenefit
Net income	$ 5,963us-gaap_NetIncomeLoss	$ 9,018us-gaap_NetIncomeLoss
Net income per share:
Basic (in Dollars per share)	$ 0.15us-gaap_EarningsPerShareBasic	$ 0.23us-gaap_EarningsPerShareBasic
Diluted (in Dollars per share)	$ 0.15us-gaap_EarningsPerShareDiluted	$ 0.23us-gaap_EarningsPerShareDiluted
Weighted-average shares outstanding:
Basic (in Shares)	39,105	38,470
Diluted (in Shares)	40,596	39,517
Cash dividends declared per common share (in Dollars per share)	$ 0.20

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