Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues
Total revenues	$ 74,355	$ 63,069	$ 141,179	$ 125,409
Cost and expenses
Cost of revenues	41,382	39,204	82,987	78,259
Research and development	12,124	11,852	23,559	26,192
Selling, general and administrative	47,042	37,440	90,874	75,365
Total cost and expenses	102,991	90,287	201,561	183,144
Loss from operations	(28,636)	(27,218)	(60,382)	(57,735)
Interest expense	(2,721)	(2,560)	(5,445)	(4,949)
Interest and other income (expense), net	836	(3,933)	1,289	(3,796)
Loss before income taxes	(30,521)	(33,711)	(64,538)	(66,480)
Income tax expense	(1,895)	(113)	(1,969)	(217)
Net loss	(32,416)	(33,824)	(66,507)	(66,697)
Unrealized gain (loss) on available-for-sale securities, net of tax	1,061	46	1,347	(92)
Comprehensive loss	$ (31,355)	$ (33,778)	$ (65,160)	$ (66,789)
Net loss per share (Note 13):
Basic (in dollars per share)	$ (0.48)	$ (0.62)	$ (1.01)	$ (1.23)
Diluted (in dollars per share)	$ (0.48)	$ (0.62)	$ (1.01)	$ (1.23)
Weighted-average number of shares used in computing basic and diluted net loss per share:
Basic (in shares)	68,224	54,551	65,542	54,342
Diluted (in shares)	68,224	54,551	65,542	54,342
Product
Revenues
Total revenues	$ 65,099	$ 60,353	$ 128,463	$ 114,622
Licensing and other
Revenues
Total revenues	9,256	2,716	12,716	10,787
Cost and expenses
Cost of revenues	$ 2,443	$ 1,791	$ 4,141	$ 3,328