Note 1 - Summary of Significant Accounting Policies - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 26, 2015
Property, plant and equipment	$ 47,203	$ 45,466
Less accumulated depreciation and amortization	(28,969)	(26,466)
Property, plant and equipment, net	18,234	19,000
Land and Land Improvements [Member]
Property, plant and equipment	4,079	4,607
Building and Building Improvements [Member]
Property, plant and equipment	7,967	8,971
Machinery and Equipment [Member]
Property, plant and equipment	$ 35,157	$ 31,888