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 Comprehensive Income [Abstract]
Net loss	$ (17,360)	$ (20,437)	$ (45,139)	$ (29,502)
Other comprehensive income:
Net change in unrealized gains on available-for-sale securities	(5)	(183)	(4)	99
Comprehensive loss	$ (17,365)	$ (20,620)	$ (45,143)	$ (29,403)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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