CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (30,500)	$ (35,340)	$ (31,573)	$ (70,671)
Other comprehensive (loss):
Change in unrealized gain (loss) on available for sale securities, net	25	30	2	(172)
Total other comprehensive loss	25	30	2	(172)
Comprehensive loss	$ (30,475)	$ (35,310)	$ (31,571)	$ (70,843)