Note 1 - Summary of Significant Accounting Policies - Inventories (Details) - USD ($) $ in Thousands	Jun. 27, 2020	Dec. 28, 2019
Raw materials and purchased parts	$ 78,317	$ 69,665
Work in process	45,978	46,591
Finished goods	17,516	14,450
Total inventories	$ 141,811	$ 130,706	[1]

[1] Derived from December 28, 2019 audited financial statements