Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Product revenue	$ 3,155	$ 741
Royalty revenue	542	144
Contract revenue	4	16
Total revenue	3,701	901
Cost of product revenue	2,588	1,037
Cost of contract revenue	1	7
Total cost of revenue	2,589	1,044
Gross profit	1,112	(143)
Research and development expense	2,597	1,898
Sales, marketing, general and administrative expense	2,068	1,921
Total operating expenses	4,665	3,819
Loss from operations	(3,553)	(3,962)
Other income, net	(3)	0
Net loss	$ (3,556)	$ (3,962)
Net loss per share - basic and diluted	$ (0.07)	$ (0.09)
Weighted-average shares outstanding - basic and diluted	47,566	44,963