Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (78,182)	$ (41,021)	$ (77,216)
Other comprehensive loss:
Net unrealized gains (losses) on available-for-sale securities	(4)		0
Foreign currency translation gain (loss)	21	(56)	(1)
Comprehensive loss	$ (78,165)	$ (41,077)	$ (77,217)