Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Product revenue	$ 0	$ 3,530	$ 0	$ 6,685
Royalty revenue	346	609	881	1,151
Contract revenue	1,107	16	1,364	20
Total revenue	1,453	4,155	2,245	7,856
Cost of product revenue	135	2,587	348	5,175
Cost of contract revenue	810	5	1,135	6
Total cost of revenue	945	2,592	1,483	5,181
Gross profit	508	1,563	762	2,675
Research and development expense	3,672	2,879	6,990	5,476
Sales, marketing, general and administrative expense	2,325	2,171	4,905	4,239
Total operating expenses	5,997	5,050	11,895	9,715
Loss from operations	(5,489)	(3,487)	(11,133)	(7,040)
Other (expense) income, net	(5)	11	(8)	8
Net loss	$ (5,494)	$ (3,476)	$ (11,141)	$ (7,032)
Net loss per share - basic and diluted	$ (0.08)	$ (0.07)	$ (0.16)	$ (0.14)
Weighted-average shares outstanding - basic and diluted	69,373	51,567	68,747	49,566

Costs incurred and are directly related to generating contract revenues.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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Revenue earned during the period from the leasing or otherwise lending to a third party the entity's rights or title to certain property. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. Examples of property from which royalties may be derived include patents and oil and mineral rights.

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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