CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 28, 2019	Sep. 28, 2018	Jun. 29, 2018
Property, plant and equipment, accumulated depreciation	$ 140,316	$ 131,322	$ 129,028
Class A
Common stock, shares issued (shares)	8,838,459	8,787,360	8,785,735
Common stock, shares outstanding (shares)	8,838,459	8,787,360	8,785,735
Treasury stock, shares (shares)	29,225	67,655	67,655
Class B
Common stock, shares issued (shares)	1,211,602	1,211,686	1,211,686
Common stock, shares outstanding (shares)	1,211,602	1,211,686	1,211,686

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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