CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CONSOLIDATED STATEMENTS OF OPERATIONS
Revenues from collaborative agreements		$ 300,000	$ 925,000
License fees and royalties	2,709,000	2,138,000	2,638,000
Total revenues	2,709,000	2,438,000	3,563,000
Operating expenses:
Research and development (including amounts for related parties: 2012-none, 2011-none, 2010-$697)	51,368,000	69,316,000	61,687,000
Acquired in-process research and development			35,000,000
Restructuring charges	2,702,000	5,449,000
General and administrative	20,397,000	23,789,000	18,043,000
Total operating expenses	74,467,000	98,554,000	114,730,000
Loss from operations	(71,758,000)	(96,116,000)	(111,167,000)
Unrealized gain on derivatives, net	13,000	643,000	190,000
Interest and other income	3,097,000	1,024,000	2,045,000
Losses recognized under equity method investment		(503,000)	(2,347,000)
Losses recognized from debt extinguishment		(1,664,000)
Interest and other expense	(233,000)	(237,000)	(98,000)
Net loss	$ (68,881,000)	$ (96,853,000)	$ (111,377,000)
Basic and diluted net loss per share (in dollars per share)	$ (0.54)	$ (0.78)	$ (1.14)
Shares used in computing basic and diluted net loss per share (in shares)	126,941,024	124,506,763	97,601,520