CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (16,466)	$ (18,792)
Other comprehensive (loss) income
Unrealized (losses) gains on available-for-sale investments, net of taxes	(237)	211
Comprehensive loss	$ (16,703)	$ (18,581)

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

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