CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenue:
Revenue from termination of ADM collaboration				$ 38,885
Grant revenue	584	461	1,308	839
Product revenue	822	373	1,611	387
Research and development revenue	238		618
License fee and royalty revenue	62	89	111	134
Total revenue	1,706	923	3,648	40,245
Costs and expenses:
Cost of product revenue	1,196	437	1,753	492
Research and development	4,945	5,006	9,802	11,051
Selling, general, and administrative	3,422	3,437	6,734	7,836
Total costs and expenses	9,563	8,880	18,289	19,379
Income (loss) from operations	(7,857)	(7,957)	(14,641)	20,866
Other income (expense):
Interest income, net	12	34	33	75
Other expense, net	(21)	(25)	(20)	(49)
Total other income (expense), net	(9)	9	13	26
Net income (loss)	$ (7,866)	$ (7,948)	$ (14,628)	$ 20,892
Net income (loss) per share:
Basic (in dollars per share)	$ (0.23)	$ (0.23)	$ (0.43)	$ 0.61
Diluted (in dollars per share)	$ (0.23)	$ (0.23)	$ (0.43)	$ 0.61
Number of shares used in per share calculations:
Basic (in shares)	34,434,271	34,183,702	34,393,998	34,160,018
Diluted (in shares)	34,434,271	34,183,702	34,393,998	34,264,428