Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 30, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (3,048)	$ (3,603)
Foreign currency translation adjustments	8	23
Comprehensive loss	$ (3,040)	$ (3,580)

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

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