Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (5,539)	$ (6,193)
Foreign currency translation adjustment	(3)	10
Comprehensive loss	$ (5,542)	$ (6,183)

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

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