CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Revenue (including amounts from a related party: three months-2012-$1,430; 2011-$2,380; nine months-2012-$4,291; 2011-$7,294)	$ 1,430	$ 6,431	$ 129,960	$ 19,150
Operating expenses:
Research and development	27,026	27,837	89,778	71,099
General and administrative	7,754	7,796	23,201	22,213
Total operating expenses	34,780	35,633	112,979	93,312
Income (loss) from operations	(33,350)	(29,202)	16,981	(74,162)
Interest income	158	81	304	344
Interest expense	(1,500)	(1,505)	(4,503)	(4,519)
Net income (loss)	$ (34,692)	$ (30,626)	$ 12,782	$ (78,337)
Net income (loss) per share:
Basic net income (loss) per share (in dollars per share)	$ (0.37)	$ (0.37)	$ 0.14	$ (0.96)
Diluted net income (loss) per share (in dollars per share)	$ (0.37)	$ (0.37)	$ 0.18	$ (0.96)
Shares used to compute basic earnings per share (in shares)	95,027	82,490	89,271	81,777
Shares used to compute diluted earnings per share (in shares)	95,027	82,490	98,381	81,777