Consolidated Statements of Comprehensive Loss (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues:
Collaborative agreements	$ 22,593	$ 2,109	$ 783
Subscription and license fees	261	113	306
Total revenues	22,854	2,222	1,089
Operating expenses:
Research and development, including stock-based compensation of $4,020, $4,376 and $3,673, respectively	89,279	89,682	82,574
Increase (decrease) in fair value of Symphony Icon, Inc. purchase liability	1,428	(2,210)	9,887
General and administrative, including stock-based compensation of $3,061, $3,045 and $2,822, respectively	19,411	17,121	17,043
Impairment loss on buildings	13,102	0	0
Total operating expenses	123,220	104,593	109,504
Loss from operations	(100,366)	(102,371)	(108,415)
Interest expense	(2,253)	(1,971)	(2,114)
Interest and other income, net	2,255	216	318
Consolidated net loss before taxes	(100,364)	(104,126)	(110,211)
Income tax benefit	70	0	0
Consolidated net loss	(100,294)	(104,126)	(110,211)
Consolidated net loss per common share, basic and diluted	$ (0.19)	$ (0.20)	$ (0.23)
Shares used in computing consolidated net loss per common share, basic and diluted	534,432	513,117	489,707
Other comprehensive gain (loss):
Unrealized gain (loss) on investments	(65)	(21)	2
Comprehensive loss	$ (100,359)	$ (104,147)	$ (110,209)