Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Consolidated Statements of Comprehensive Loss [Abstract]
Net loss	$ (115,088)	$ (90,137)	$ (89,860)
Other comprehensive income (loss):
Net unrealized gain (loss) on available-for-sale securities	(3)	(39)	155
Total comprehensive loss	$ (115,091)	$ (90,176)	$ (89,705)