CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (128,694)	$ (103,916)
Other comprehensive gain (loss):
Change in unrealized gain (loss) on available for sale securities, net	(183)	260
Total other comprehensive gain (loss)	(183)	260
Comprehensive loss	$ (128,877)	$ (103,656)