CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net Loss	$ (2,641)	$ (1,108)	$ (13,401)	$ (2,350)
Other Comprehensive (Loss) Income
Foreign exchange translation adjustment	(169)	717	344	719
Comprehensive Loss Attributable to the Company	$ (2,810)	$ (391)	$ (13,057)	$ (1,631)