Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenues
Total revenues	$ 66,824	$ 62,340
Cost and expenses
Cost of revenues	41,605	39,055
Research and development	11,435	14,340
Selling, general and administrative	43,832	37,925
Total cost and expenses	98,570	92,857
Loss from operations	(31,746)	(30,517)
Interest expense	(2,724)	(2,389)
Interest and other income	453	137
Loss before income taxes	(34,017)	(32,769)
Income tax expense	(74)	(104)
Net loss	(34,091)	(32,873)
Unrealized gain (loss) on available-for-sale securities, net of tax	286	(138)
Comprehensive loss	$ (33,805)	$ (33,011)
Net loss per share (Note 13):
Basic (in dollars per share)	$ (0.54)	$ (0.61)
Diluted (in dollars per share)	$ (0.54)	$ (0.61)
Weighted-average number of shares used in computing basic and diluted net loss per share:
Basic (in shares)	62,831	54,132
Diluted (in shares)	62,831	54,132
Product
Revenues
Total revenues	$ 63,364	$ 54,269
Licensing and other
Revenues
Total revenues	3,460	8,071
Cost and expenses
Cost of revenues	$ 1,698	$ 1,537