CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Revenues:
License fees	$ 0	$ 730	$ 0	$ 1,460
Total revenues	0	730	0	1,460
Operating expenses:
Research and development	10,161	10,527	18,733	20,840
General and administrative	4,200	3,370	8,353	6,762
Total operating expenses	14,361	13,897	27,086	27,602
Loss from operations	(14,361)	(13,167)	(27,086)	(26,142)
Other income:
Gain (loss) on sale/disposal of assets	5	19	(5)	32
Deferred gain on real estate	805	781	1,609	1,563
Investment income, net	167	121	256	224
Other income, net	3	4	3	6
Total other income	980	925	1,863	1,825
Net loss	(13,381)	(12,242)	(25,223)	(24,317)
Net loss per common share:
Basic and diluted	$ (0.18)	$ (0.18)	$ (0.35)	$ (0.36)
Shares used in the calculation of net loss per common share:
Basic and diluted	75,879	66,799	73,085	66,700
Other comprehensive loss:
Net loss	(13,381)	(12,242)	(25,223)	(24,317)
Net unrealized gains (losses) on available-for-sale securities	68	0	(131)	(42)
Comprehensive loss	$ (13,313)	$ (12,242)	$ (25,354)	$ (24,359)