Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenue:
Revenue	$ 22,604	$ 30,345	$ 49,209	$ 58,033
Costs and expenses:
Cost of product and service revenue	10,712	9,605	21,729	18,314
Research and development	15,739	17,029	33,241	33,056
Selling, general and administrative	19,912	22,499	45,633	45,935
Total costs and expenses	46,363	49,133	100,603	97,305
Loss from operations	(23,759)	(18,788)	(51,394)	(39,272)
Other income (expense):
Interest income	479	828	1,183	1,351
Interest expense	(4,116)	(1,889)	(6,999)	(3,637)
Other income (expense), net	332	(120)	(1,275)	(230)
Loss on extinguishment of debt and termination of revolving loan facility	0	0	(7,143)	0
Total other expense, net	(3,305)	(1,181)	(14,234)	(2,516)
Net loss before provision for income tax	(27,064)	(19,969)	(65,628)	(41,788)
Provision for income tax	(69)	(68)	(129)	(147)
Net loss	$ (27,133)	$ (20,037)	$ (65,757)	$ (41,935)
Net loss per share - basic and diluted (in dollars per share)	$ (0.72)	$ (0.57)	$ (1.76)	$ (1.26)
Weighted average shares used in computing basic and diluted net loss per share (in shares)	37,785	35,174	37,392	33,382
Total product and service revenue
Revenue:
Revenue	$ 21,144	$ 22,370	$ 45,640	$ 43,720
Collaboration revenue
Revenue:
Revenue	$ 1,460	$ 7,975	$ 3,569	$ 14,313