CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) - USD ($) $ in Thousands	Dec. 27, 2019	Sep. 27, 2019	Dec. 28, 2018
Property, plant and equipment, accumulated depreciation	$ 146,453	$ 143,028	$ 133,958
Class A
Common stock, shares issued (shares)	8,858,611	8,834,169	8,825,790
Common stock, shares outstanding (shares)	8,858,611	8,834,169	8,825,790
Treasury stock, shares (shares)	36,354	29,225	29,225
Class B
Common stock, shares issued (shares)	1,211,602	1,211,602	1,211,602
Common stock, shares outstanding (shares)	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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