CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net loss	$ (19,792)	$ (4,651)	$ (22,636)	$ (12,310)
Other comprehensive loss:
Unrealized gain on investments	35	0	38	0
Comprehensive loss	$ (19,757)	$ (4,651)	$ (22,598)	$ (12,310)

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

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