Condensed Consolidated Statements of Operations (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Revenues:
Product revenues	$ 68,152,000us-gaap_SalesRevenueGoodsNet	$ 67,002,000us-gaap_SalesRevenueGoodsNet
Operating expenses:
Cost of product revenues	12,762,000us-gaap_CostOfGoodsSold	12,055,000us-gaap_CostOfGoodsSold
Research and development	19,118,000us-gaap_ResearchAndDevelopmentExpense	14,005,000us-gaap_ResearchAndDevelopmentExpense
Selling and marketing	35,352,000us-gaap_SellingAndMarketingExpense	33,408,000us-gaap_SellingAndMarketingExpense
General and administrative	15,589,000us-gaap_GeneralAndAdministrativeExpense	14,728,000us-gaap_GeneralAndAdministrativeExpense
Total operating expenses	82,821,000us-gaap_CostsAndExpenses	74,196,000us-gaap_CostsAndExpenses
Loss from operations	(14,669,000)us-gaap_OperatingIncomeLoss	(7,194,000)us-gaap_OperatingIncomeLoss
Interest income	54,000us-gaap_InvestmentIncomeNonoperating	50,000us-gaap_InvestmentIncomeNonoperating
Other expense, net	(374,000)us-gaap_OtherNonoperatingIncomeExpense	(226,000)us-gaap_OtherNonoperatingIncomeExpense
Loss before income taxes	(14,989,000)	(7,370,000)
Income tax (benefit) expense	(5,496,000)us-gaap_IncomeTaxExpenseBenefit	75,000us-gaap_IncomeTaxExpenseBenefit
Net loss	$ (9,493,000)	$ (7,445,000)
Basic and diluted net loss per share (in dollars per share)	$ (0.30)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.24)us-gaap_EarningsPerShareBasicAndDiluted
Shares used in computing basic and diluted net loss per share	32,055	31,087

Total costs related to goods produced and sold during the reporting period.

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