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Schedule II - Valuation and Qualifying Accounts (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 28, 2019
Dec. 29, 2018
Dec. 30, 2017
Dec. 31, 2016
Allowance for doubtful accounts        
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]        
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount $ 2,206 $ 1,535 $ 2,116 $ 1,698
SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense (1,021) (486) (251)  
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction 350 95 167  
Allowance for sales returns and allowances        
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]        
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount 700 432 424 $ 605
SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense (1,696) (1,416) (1,646)  
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction $ 1,428 $ 1,408 $ 1,827