Condensed Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Revenue:
Product sales and royalty revenue	$ 6,172	$ 15,026	$ 17,980	$ 37,836
Non-cash royalty revenue related to sale of future royalties	6,143	4,523	16,753	12,744
License, collaboration and other revenue	120,556	41,360	146,422	67,195
Total revenue	132,871	60,909	181,155	117,775
Operating costs and expenses:
Cost of goods sold	9,220	12,877	22,235	29,549
Research and development	34,200	43,914	109,240	141,762
General and administrative	9,130	10,643	28,677	30,700
Total operating costs and expenses	52,550	67,434	160,152	202,011
Income (loss) from operations	80,321	(6,525)	21,003	(84,236)
Non-operating income (expense):
Interest income	133	116	399	639
Interest expense	(4,391)	(4,587)	(13,412)	(13,888)
Non-cash interest expense on liability related to sale of future royalties	(5,203)	(5,616)	(15,725)	(16,644)
Other income (expense), net	(7)	262	136	385
Total non-operating expense, net	(9,468)	(9,825)	(28,602)	(29,508)
Income (loss) before provision for income taxes	70,853	(16,350)	(7,599)	(113,744)
Provision for income taxes	248	193	634	610
Net income (loss)	$ 70,605	$ (16,543)	$ (8,233)	$ (114,354)
Net income (loss) per share
Basic	$ 0.55	$ (0.14)	$ (0.07)	$ (0.99)
Diluted	$ 0.53	$ (0.14)	$ (0.07)	$ (0.99)
Weighted average shares outstanding used in computing net income (loss) per share
Basic	127,504	115,812	126,043	115,557
Diluted	132,177	115,812	126,043	115,557