CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenue:
Product sales	$ 3,901	$ 2,312	$ 12,571	$ 5,716
Revenue from collaborative arrangements	15,174	8,386	30,385	32,517
Total revenue	19,075	10,698	42,956	38,233
Costs and expenses:
Cost of goods sold	332	581	1,748	1,456
Research and development	31,951	30,367	99,698	96,763
Selling, general and administrative	20,286	22,845	64,143	66,139
Total costs and expenses	52,569	53,793	165,589	164,358
Loss from operations	(33,494)	(43,095)	(122,633)	(126,125)
Interest and other income	344	104	839	518
Loss before income taxes	(33,150)	(42,991)	(121,794)	(125,607)
Provision for income taxes	812	4,323	1,542	11,786
Net loss	(33,962)	(47,314)	(123,336)	(137,393)
Share-based compensation expense	$ 9,895	$ 12,251	$ 31,129	$ 42,539
Net loss per share:
Basic and diluted net loss per share (in dollars per share)	$ (0.73)	$ (1.40)	$ (2.86)	$ (4.12)
Shares used to compute basic and diluted net loss per share (in shares)	46,470	33,689	43,080	33,353
Net unrealized gain (loss) on available-for-sale investments	$ (142)	$ 19	$ 109	$ 125
Total comprehensive loss	(34,104)	(47,295)	(123,227)	(137,268)
Research and development
Costs and expenses:
Share-based compensation expense	4,933	6,035	15,052	20,334
Selling, general and administrative
Costs and expenses:
Share-based compensation expense	$ 4,962	$ 6,216	$ 16,077	$ 22,205