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
Income Statement [Abstract]
Net loss	$ (3,188)	$ (12,677)	$ (20,598)	$ (25,717)
Other comprehensive income/(loss):
Unrealized gain on available-for-sale securities		7		11
Reclassification of realized gains included in net loss		(10)		(83)
Comprehensive loss	$ (3,188)	$ (12,680)	$ (20,598)	$ (25,789)