Note 1 - Summary of Significant Accounting Policies - Inventories (Details) - USD ($) $ in Thousands	Jun. 25, 2022	Dec. 25, 2021
Raw materials and purchased parts	$ 93,648	$ 92,798
Work in process	41,760	40,732
Finished goods	27,258	27,523
Total inventories	$ 162,666	$ 161,053	[1]

[1] Derived from December 25, 2021 audited financial statements