Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Type of Revenue [Extensible List]	us-gaap:CollaborativeArrangementMember	us-gaap:CollaborativeArrangementMember
Operating costs and expenses:
Cost of goods sold	$ 187	$ 170
Research and development	58,056	63,610
Selling, general and administrative	39,847	70,130
Total operating costs and expenses	98,090	133,910
Loss from operations	(96,507)	(131,624)
Interest income, net	708	4,729
Other income, net	35	155
Net loss	$ (95,764)	$ (126,740)
Net loss per share—basic and diluted	$ (1.64)	$ (2.44)
Weighted average number of common shares outstanding—basic and diluted	58,374,219	51,908,760
Comprehensive loss:
Net loss	$ (95,764)	$ (126,740)
Other comprehensive items:
Unrealized gain (loss) on marketable securities	(651)	(2,087)
Total other comprehensive gain (loss)	(651)	(2,087)
Total comprehensive loss	(96,415)	(128,827)
Product Revenue [Member]
Total revenue	$ 1,583	$ 2,286