CONDENSED 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	$ (17,226)	$ (16,461)
Other comprehensive (loss) gain:
Unrealized holding (loss) gain on marketable securities	(21)	11
Comprehensive loss	$ (17,247)	$ (16,450)

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

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