Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues:
Product revenues	$ 83,821	$ 82,136	$ 253,287	$ 244,916
Contract revenues		122		210
Total revenues	83,821	82,258	253,287	245,126
Operating expenses:
Cost of product revenues	13,433	13,425	40,904	45,177
Research and development	17,212	14,746	47,868	45,303
Selling and marketing	38,303	38,838	120,464	116,327
General and administrative	17,505	18,268	52,651	55,243
Total operating expenses	86,453	85,277	261,887	262,050
Loss from operations	(2,632)	(3,019)	(8,600)	(16,924)
Interest income	263	117	627	282
Gain on sales of equity securities			2,807	2,009
Other income (expense), net	340	(111)	792	(174)
Loss before income taxes	(2,029)	(3,013)	(4,374)	(14,807)
Income tax expense (benefit)	162	(193)	1,362	464
Net loss	$ (2,191)	$ (2,820)	$ (5,736)	$ (15,271)
Basic and diluted net loss per share (in dollars per share)	$ (0.06)	$ (0.08)	$ (0.17)	$ (0.46)
Shares used in computing basic and diluted net loss per share (in shares)	34,675	33,391	34,373	33,141