CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Oct. 01, 2021	Jan. 01, 2021
Accumulated depreciation	$ 167,216	$ 163,891	$ 160,822
Treasury stock (in shares)	43,493	42,598	41,977
Class A
Common stock, issued (in shares)	8,949,163	8,915,636	8,900,608
Common stock, shares outstanding (in shares)	8,949,163	8,915,636	8,900,608
Class B
Common stock, issued (in shares)	1,207,882	1,211,564	1,211,564
Common stock, shares outstanding (in shares)	1,207,882	1,211,564	1,211,564

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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