Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenue:
Product and service	$ 56,639	$ 44,497	$ 31,403
Collaboration	6,028	3,096	0
Total revenue	62,667	47,593	31,403
Costs and expenses:
Cost of product and service revenue	26,126	21,149	15,009
Research and development	24,597	21,404	14,979
Selling, general and administrative	53,186	51,063	29,912
Total costs and expenses	103,909	93,616	59,900
Loss from operations	(41,242)	(46,023)	(28,497)
Other income (expense):
Interest income	233	272	68
Interest expense	(4,017)	(4,140)	(1,942)
Other expense	(389)	(147)	(66)
Revaluation of preferred stock warrant liability	0	0	1,156
Total other income (expense)	(4,173)	(4,015)	(784)
Net loss before provision for income taxes	(45,415)	(50,038)	(29,281)
Provision for income taxes	(166)	0	0
Net loss	(45,581)	(50,038)	(29,281)
Accretion of mandatorily redeemable convertible preferred stock	0	0	(4,653)
Net loss attributable to common stockholders	$ (45,581)	$ (50,038)	$ (33,934)
Net loss per share-basic and diluted	$ (2.40)	$ (2.80)	$ (4.44)
Weighted average shares used in computing basic and diluted net loss per share	19,027	17,839	7,643