Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenue:
Product and service	$ 12,136	$ 10,832
Collaboration	2,561	761
Total revenue	14,697	11,593
Costs and expenses:
Cost of product and service revenue	5,870	5,340
Research and development	7,208	5,916
Selling, general and administrative	14,904	14,125
Total costs and expenses	27,982	25,381
Loss from operations	(13,285)	(13,788)
Other income (expense):
Interest income	68	67
Interest expense	(1,315)	(984)
Other expense, net	(71)	(189)
Total other income (expense), net	(1,318)	(1,106)
Net loss before provision for income tax	(14,603)	(14,894)
Provision for income tax	0	0
Net loss	$ (14,603)	$ (14,894)
Net loss per share - basic and diluted (in dollars per share)	$ (0.74)	$ (0.81)
Weighted average shares used in computing basic and diluted net loss per share (in shares)	19,669	18,310