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	$ (12,436)	$ (7,076)	$ (25,404)	$ (8,992)
Foreign currency translation adjustments related to continuing operations	18	10	93	(12)
Comprehensive loss	$ (12,418)	$ (7,066)	$ (25,311)	$ (9,004)

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

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