Note 1 - Summary of Significant Accounting Policies - Components of Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Sep. 30, 2024
Raw materials	$ 37,993	$ 50,193
Work-in-process	2,369	1,088
Finished goods	14,107	19,524
Inventories, gross	54,469	70,805
Inventory reserve	(12,438)	(14,709)
Inventories, net	$ 42,031	$ 56,096

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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

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Amount of valuation reserve for inventory.

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