CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue:
Total revenue	$ 18,662	$ 34,288	$ 31,176
Expenses:
Research and development	113,842	173,797	168,435
Gain on Catalent transaction	(9,016)
General and administrative	34,417	34,409	34,451
Total expenses	139,243	208,206	202,886
Loss from operations	(120,581)	(173,918)	(171,710)
Other income (expense):
Investment income	1,512	2,674	1,946
Interest expense	(13,612)	(13,612)	(14,072)
Other income (expense)	(13)	108	67
Net loss	$ (132,694)	$ (184,748)	$ (183,769)
Basic and diluted net loss per share	$ (5.51)	$ (9.99)	$ (12.56)
Basic and diluted weighted average number of common shares outstanding	24,100	18,488	14,633
Government Contract [Member]
Revenue:
Total revenue	$ 7,500
Grant and other [Member]
Revenue:
Total revenue	$ 11,162	$ 34,288	$ 31,176