Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 02, 2021	Sep. 26, 2020	Oct. 02, 2021	Sep. 26, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (2,165)	$ (1,719)	$ (2,782)	$ (6,150)
Foreign currency translation adjustments	20	(41)	48	(48)
Comprehensive loss	$ (2,145)	$ (1,760)	$ (2,734)	$ (6,198)

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

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