CONSOLIDATED CONDENSED BALANCE SHEETS (Parentheticals) - USD ($) $ in Thousands	Jun. 28, 2025	Dec. 28, 2024
Expense for expected credit losses	$ 539	$ 454
Common Class A
Common stock, par value (in dollars per share)	$ 3	$ 3
Common stock, shares authorized (in shares)	80,000,000	80,000,000
Common stock, shares issued (in shares)	13,976,735	13,997,446
Common stock, shares outstanding (in shares)	13,976,735	13,997,446
Common Class B
Common stock, par value (in dollars per share)	$ 3	$ 3
Common stock, shares authorized (in shares)	16,000,000	16,000,000
Common stock, shares issued (in shares)	1,240,285	1,249,302
Common stock, shares outstanding (in shares)	1,240,285	1,249,302