Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenues:
Total revenue	$ 1,976	$ 5,718
Operating expenses:
Research and development	134,870	64,979
General and administrative	25,739	12,649
Total operating expenses	160,609	77,628
Loss from operations	(158,633)	(71,910)
Other income (expense):
Interest income	164	1,755
Other expense, net	(10,246)	(7,069)
Total other income (expense)	(10,082)	(5,314)
Loss before provision for income taxes	(168,715)	(77,224)
Provision for income taxes	(196)	(16)
Net loss	$ (168,911)	$ (77,240)
Net loss per share, basic and diluted	$ (1.32)	$ (0.71)
Weighted-average shares outstanding, basic and diluted	127,742,614	108,387,913
Grant Revenue [Member]
Revenues:
Total revenue	$ 1,371	$ 5,231
Contract Revenue [Member]
Revenues:
Total revenue	$ 605	$ 487