Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue
Product revenue	$ 12,291	$ 12,425	$ 24,761	$ 23,384
License and other revenue	68	87	133	192
Total revenue	12,359	12,512	24,894	23,576
Cost of revenue	7,475	4,720	13,827	9,095
Gross profit	4,884	7,792	11,067	14,481
Operating expenses
Sales and marketing	5,159	3,300	9,853	7,009
General and administrative	3,978	3,876	7,988	7,296
Research and development	13,014	13,204	24,049	25,472
Total operating expenses	22,151	20,380	41,890	39,777
Loss from operations	(17,267)	(12,588)	(30,823)	(25,296)
Other income (expense)
Interest income	54	26	106	55
Interest expense	(755)	(308)	(1,261)	(585)
Other income	56	(42)	151	(9)
Total other expense	(645)	(324)	(1,004)	(539)
Loss before provision for income taxes	(17,912)	(12,912)	(31,827)	(25,835)
Income tax expense	77	(5)	78	31
Net loss	$ (17,989)	$ (12,907)	$ (31,905)	$ (25,866)
Net loss per share, basic and diluted	$ (0.37)	$ (0.30)	$ (0.67)	$ (0.60)
Weighted average number of shares outstanding, basic and diluted	48,067	42,864	47,460	42,768
Other comprehensive loss
Net loss	$ 17,989	$ 12,907	$ 31,905	$ 25,866
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax	3	(34)	94	13
Net unrealized gains (losses) on marketable securities, net of tax	1	(5)	(15)	(21)
Comprehensive loss	$ (17,985)	$ (12,946)	$ (31,826)	$ (25,874)