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Valuation and Qualifying Accounts (Details) - USD ($)
12 Months Ended
Dec. 28, 2019
Dec. 29, 2018
Dec. 30, 2017
Dec. 31, 2016
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]        
Accounts Receivable, Allowance for Credit Loss $ 938,000 $ 304,000 $ 149,000 $ 136,000
Allowance for Doubtful Accounts Receivable, Period Increase (Decrease) 951,000 268,000 13,000  
Accounts Receivable, Allowance for Credit Loss, Recovery $ (317,000) $ (113,000) $ 0