CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Revenue:
Revenue from termination of ADM collaboration		$ 38,885
Grant revenue	724	378
Product revenue	790	14
Research and development revenue	380
License fee and royalty revenue	49	45
Total revenue	1,943	39,322
Costs and expenses:
Cost of product revenue	557	55
Research and development	4,859	6,045
Selling, general, and administrative	3,312	4,399
Total costs and expenses	8,728	10,499
Income (loss) from operations	(6,785)	28,823
Other income:
Interest income, net	10	17
Other income, net	12
Net income (loss)	$ (6,763)	$ 28,840
Net income (loss) per share:
Basic (in dollars per share)	$ (0.20)	$ 0.84
Diluted (in dollars per share)	$ (0.20)	$ 0.84
Number of shares used in per share calculations:
Basic (in shares)	34,353,277	34,136,333
Diluted (in shares)	34,353,277	34,265,638