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	$ (35,331)	$ (23,852)
Other comprehensive gain (loss):
Change in unrealized gain (loss) on available for sale securities, net	(202)	83
Total other comprehensive gain (loss)	(202)	83
Comprehensive loss	$ (35,533)	$ (23,769)

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

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