CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (29,627)	$ (14,148)	$ (79,749)	$ (36,791)
Other comprehensive gain:
Change in unrealized gain (loss) on available for sale securities, net	68	28	331	52
Total other comprehensive gain	68	28	331	52
Comprehensive loss	$ (29,559)	$ (14,120)	$ (79,418)	$ (36,739)

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

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