Note 1 - Summary of Significant Accounting Policies - Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 25, 2021
Raw materials and purchased parts	$ 106,041	$ 92,798
Work in process	36,024	40,732
Finished goods	28,076	27,523
Total inventories	$ 170,141	$ 161,053

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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