Additional Balance Sheet Information (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 26, 2019
Additional Balance Sheet Information
Trade receivables, net of allowances of $762 and $361, respectively	$ 405	$ 9,327
Other receivables	5,954	20,138
Accounts, Notes, Loans and Financing Receivable, Net, Current, Total	$ 6,359	$ 29,465

Amount, after allowance for credit loss, of accounts and financing receivables, classified as current. Includes, but is not limited to, notes and loan receivable.

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