Note 1 - Summary of Significant Accounting Policies - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Sep. 25, 2021	Dec. 26, 2020
Property, plant and equipment	$ 113,440	$ 114,636
Less accumulated depreciation and amortization	(48,282)	(47,720)
Property, plant and equipment, net	65,158	66,916	[1]
Land and Land Improvements [Member]
Property, plant and equipment	7,875	8,141
Building and Building Improvements [Member]
Property, plant and equipment	26,749	41,153
Machinery and Equipment [Member]
Property, plant and equipment	$ 78,816	$ 65,342

[1] Derived from December 26, 2020 audited financial statements