Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (1,785)	$ (3,074)	$ (7,252)	$ (9,957)
Foreign currency translation adjustments	36	86	32	127
Comprehensive loss	$ (1,749)	$ (2,988)	$ (7,220)	$ (9,830)

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

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