CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 28, 2020	Sep. 27, 2019	Jun. 28, 2019
Property, plant and equipment, accumulated depreciation	$ 152,646	$ 143,028	$ 140,316
Class A
Common stock, shares issued	8,873,197	8,834,169	8,838,459
Common stock, shares outstanding	8,873,197	8,834,169	8,838,459
Treasury stock, shares	36,354	29,225	29,225
Class B
Common stock, shares issued	1,211,602	1,211,602	1,211,602
Common stock, shares outstanding	1,211,602	1,211,602	1,211,602

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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