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Summary of Significant Accounting Policies - Reconciliation of Changes in Warranty Liability (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 28, 2019
Dec. 29, 2018
Reconciliation of the changes in the Company's warranty liability    
Balance, beginning of period $ 860 $ 1,735
Accruals for product warranties 283 454
Cost of warranty claims (296) (884)
Adjustment to pre-existing warranties (311) (445)
Balance, end of period $ 536 $ 860