Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement [Abstract]
Product revenue	$ 2,078	$ 16	$ 5,001	$ 18
Royalty revenue	309	0	777	26
Contract revenue	11	722	1,564	1,063
Development revenue	0	230	0	1,691
Total revenue	2,398	968	7,342	2,798
Cost of product revenue	1,810	5	4,921	28
Cost of contract revenue	3	363	792	507
Total cost of revenue	1,813	368	5,713	535
Gross profit	585	600	1,629	2,263
Research and development expense	2,231	2,369	6,140	7,148
Sales, marketing, general and administrative expense	1,873	1,587	5,740	5,387
Gain on sale of previously reserved inventory	(1)	0	(1)	(455)
Total operating expenses	4,103	3,956	11,879	12,080
Loss from operations	(3,518)	(3,356)	(10,250)	(9,817)
Loss on warrant exchange		0	0	(4,967)
Other income, net	5	1	6	10
Net loss	$ (3,513)	$ (3,355)	$ (10,244)	$ (14,774)
Net loss per share - basic and diluted	$ (0.07)	$ (0.08)	$ (0.22)	$ (0.36)
Weighted-average shares outstanding - basic and diluted	47,216	43,858	46,292	40,605