Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 28, 2020	Dec. 28, 2019
Consolidated Balance Sheets
Receivables, allowance (in dollars)	$ 634	$ 494
Common shares, par value (in dollars per share)	$ 0.25	$ 0.25
Common shares, authorized shares	3,000,000	3,000,000
Common shares, issued shares	2,574,264	2,574,264
Treasury, shares	898,780	860,910

Amount of allowance for credit loss on accounts receivable, classified as current.

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