Note 1 - Summary of Significant Accounting Policies - Inventories (Details) - USD ($) $ in Thousands	Dec. 25, 2021	Dec. 26, 2020
Raw materials and purchased parts	$ 92,798	$ 83,755
Work in process	40,732	44,315
Finished goods	27,523	14,430
Total inventories	$ 161,053	$ 142,500

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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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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