Condensed 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	$ (2,244)	$ (2,375)
Other comprehensive loss:
Changes in foreign currency translation adjustment	(137)	(64)
Comprehensive loss	$ (2,381)	$ (2,439)

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

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