Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue:
Total revenue	$ 9,750
Type of Revenue [Extensible List]	us-gaap:LicenseMember
Operating expenses:
Research and development	$ 53,455	$ 71,015	$ 76,290
Research and development related to asset acquisition	50,875
General and administrative	20,853	20,372	16,605
Total operating expenses	125,183	91,387	92,895
Loss from operations	(115,433)	(91,387)	(92,895)
Interest and other income, net	345	1,250	3,035
Net loss	$ (115,088)	$ (90,137)	$ (89,860)
Net loss per share, basic and diluted	$ (1.56)	$ (1.31)	$ (1.90)
Weighted average common shares used to compute net loss per share, basic and diluted	73,869	68,814	47,312