Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (7,701)	$ (14,674)
Other comprehensive loss:
Unrealized losses related to short-term investments	(22)
Total other comprehensive loss	(22)
Comprehensive loss	$ (7,723)	$ (14,674)

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

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