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	$ (14,567)	$ (9,355)	$ (39,971)	$ (18,347)
Foreign currency translation adjustments related to continuing operations	(37)	(47)	56	(59)
Comprehensive loss	$ (14,604)	$ (9,402)	$ (39,915)	$ (18,406)

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

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