Note 2 - Certain Significant Estimates - Customer Allowances (Details) - Reserve For Customer Allowances [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 25, 2021	Dec. 26, 2020	Dec. 28, 2019
Beginning balance	$ 2,296	$ 1,292	$ 1,550
Additions	12,930	11,940	7,292
Deductions	(12,886)	(10,936)	(7,550)
Ending balance	$ 2,340	$ 2,296	$ 1,292