Statements Of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended			209 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2011
Revenue:
Contract R&D revenue	$ 146	$ 0	$ 0	$ 1,354
Operating expenses:
Research and development	1,867	3,759	10,555	176,880
General and administrative	2,102	2,771	5,140	95,790
Total operating expenses	3,969	6,530	15,695	272,670
Other income (expense):
Gain / (loss) on disposition of assets	14	(83)	(69)	(286)
Non-cash amortization of deemed discount and deferred issuance costs on convertible debentures	0	0	0	(7,627)
Interest income	6	16	138	17,385
Interest expense	0	0	0	(388)
Total other income, net	20	(67)	69	9,084
Net loss	$ 3,803	$ 6,597	$ 15,626	$ 262,232
Net loss per share, basic and diluted	$ 0.11	$ 0.20	$ 0.53
Weighted average number of common shares outstanding, basic and diluted	35,459	32,803	29,319