Note 1 - Basis of Preparation of Financial Statements (Details Textual) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended |
|---|---|---|
Mar. 31, 2026 |
Sep. 30, 2026 |
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| Hecla Quebec Inc. [Member] | ||
| Disposal Group, Including Discontinued Operations [Line Items] | ||
| Cash consideration from sale of business | $ 601.7 | |
| Loss on sale of business | $ 192.5 | |
| Minera Hecla and Industrias Hecla [Member] | ||
| Disposal Group, Including Discontinued Operations [Line Items] | ||
| Cash consideration from sale of business | $ 5.2 | |
| Loss on sale of business | $ 2.4 |
| X | ||||||||||
- Definition Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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- Details
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