Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (2,419)	$ (3,280)	$ (5,467)	$ (6,883)
Foreign currency translation adjustments	(12)	18	(4)	41
Comprehensive loss	$ (2,431)	$ (3,262)	$ (5,471)	$ (6,842)

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

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