Note 10 - Product Inventories - Schedule of Our Major Components of Product Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Inventory [Line Items]
Product inventories	$ 40,404	$ 34,962
Concentrates
Inventory [Line Items]
Product inventories	27,871	15,030
Stockpiled ore
Inventory [Line Items]
Product inventories	10,036	13,168
In-process
Inventory [Line Items]
Product inventories	$ 2,497	$ 6,764

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/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481372/852-10-55-10

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(6))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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