Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenues:
Product revenues	$ 85,487	$ 81,886	$ 169,467	$ 162,780
Contract revenues		88		88
Total revenues	85,487	81,974	169,467	162,868
Operating expenses:
Cost of product revenues	13,798	15,598	27,471	31,752
Research and development	15,781	14,948	30,655	30,557
Selling and marketing	40,656	37,989	82,163	77,489
General and administrative	18,395	18,537	35,146	36,975
Total operating expenses	88,630	87,072	175,435	176,773
Loss from operations	(3,143)	(5,098)	(5,968)	(13,905)
Interest income	206	87	364	165
Gain on sales of equity securities		676	2,807	2,009
Other income (expense), net	357	(150)	452	(63)
Loss before income taxes	(2,580)	(4,485)	(2,345)	(11,794)
Income tax expense	159	1,615	1,200	657
Net loss	$ (2,739)	$ (6,100)	$ (3,545)	$ (12,451)
Basic and diluted net loss per share (in dollars per share)	$ (0.08)	$ (0.18)	$ (0.10)	$ (0.38)
Shares used in computing basic and diluted net loss per share (in shares)	34,428	33,130	34,219	33,015