Note 10 - Product Inventories - Schedule of Our Major Components of Product Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Inventory [Line Items]
Product inventories	$ 23,818	$ 26,518
Concentrates
Inventory [Line Items]
Product inventories	15,696	15,656
Stockpiled ore
Inventory [Line Items]
Product inventories	$ 8,122	$ 10,862

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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