Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 25, 2021	Dec. 26, 2020
Allowance on trade accounts receivable	$ 6,543	$ 8,670
Allowance on other receivables	7,696	7,239
Accumulated depreciation and amortization on operating property	$ 332,785	$ 299,407
Common stock, par value	$ 0.01	$ 0.01
Common stock, authorized shares	160,000,000	160,000,000
Common stock, issued shares	68,231,013	68,183,702
Treasury stock, shares	30,122,427	29,797,639

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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