Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (83,988)	$ (103,270)
Other comprehensive gain (loss):
Unrealized (loss) gain on available-for-sale investments	(117)	(75)
Cumulative translation adjustments	(1)	29
Comprehensive loss	$ (84,106)	$ (103,316)

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

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+ Details