Stock Plans and Stock Compensation Expense (Stock Performance Units) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 26, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum market value (in dollars per share)	$ 5.00	$ 5.00
Stock Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonemployee directors fees		$ 18
Value received in stock performance units		$ 18
Stock performance units, outstanding (in shares)	130,320