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Note 13 - Guarantor Subsidiaries (Details Textual) - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2017 | Dec. 31, 2015
Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions | 100.00% |
Hecla Limited [Member] |  |
Sale of Stock, Percentage of Ownership before Transaction |  | 100.00%
Proceeds from Divestiture of Businesses |  | $ 240.8
Capital Requirements, Limited Funding Period |  | 5 years
Hecla Alaska LLC [Member] | Greens Creek [Member] |  |
Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions | 29.7331% |

X
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- 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 + Details
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