Selected Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Selected Quarterly Financial Data [Line Items]
Total revenue	$ 25,009	$ 24,921	$ 28,330	$ 23,647	$ 23,462	$ 30,033	$ 48,847	$ 50,573	$ 101,907	$ 152,915	$ 114,617
Cost of goods sold	6,163	5,311	7,667	5,756	4,323	5,570	5,773	3,811	24,897	19,477	21,374
Research and development expenses	99,614	103,738	101,313	95,604	102,724	100,531	96,436	108,987	400,269	408,678	434,566
Operating loss	(112,910)	(113,596)	(110,205)	(109,392)	(110,721)	(103,050)	(77,709)	(133,631)	(446,103)	(425,111)	(440,035)
Net loss	$ (145,645)	$ (129,706)	$ (125,519)	$ (122,967)	$ (117,203)	$ (108,586)	$ (80,000)	$ (138,651)	$ (523,837)	$ (444,440)	$ (440,667)
Net loss per share
Basic ( in dollars per share)	$ (790)	$ (700)	$ (690)	$ (680)	$ (0.65)	$ (0.61)	$ (0.45)	$ (0.78)	$ (2.86)	$ (2.49)	$ (2.52)
Diluted (in dollars per share)	$ (790)	$ (700)	$ (690)	$ (680)	$ (0.65)	$ (0.61)	$ (0.45)	$ (0.78)	$ (2.86)	$ (2.49)	$ (2.52)
Product sales
Selected Quarterly Financial Data [Line Items]
Total revenue	$ 5,890	$ 5,194	$ 7,846	$ 4,795	$ 2,884	$ 5,691	$ 5,485	$ 3,444	$ 23,725	$ 17,504	$ 20,117