Note 1 - Summary of Significant Accounting Policies - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 30, 2017	Dec. 31, 2016
Property, plant and equipment	$ 67,129	$ 47,203
Less accumulated depreciation and amortization	(32,957)	(28,969)
Property, plant and equipment, net	34,172	18,234
Land and Land Improvements [Member]
Property, plant and equipment	8,017	4,079
Building and Building Improvements [Member]
Property, plant and equipment	13,779	7,967
Machinery and Equipment [Member]
Property, plant and equipment	$ 45,333	$ 35,157