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 Income And Comprehensive Income [Abstract]
NET LOSS	$ (16,879)	$ (8,935)	$ (25,268)	$ (18,106)
OTHER COMPREHENSIVE INCOME (LOSS):
Foreign currency translation adjustments	(12)	18	13	76
Other comprehensive income (loss)	(12)	18	13	76
COMPREHENSIVE LOSS	$ (16,891)	$ (8,917)	$ (25,255)	$ (18,030)

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

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