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Note 4 - Environmental and Reclamation Activities - Liabilities Accrued for Reclamation and Closure Costs (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | --- | --- | ---
Operating properties: |  |  |  |
Reclamation and closure costs | $ 86,045 | $ 85,580 | $ 95,538 | $ 57,250
Non-operating properties: |  |  |  |
Reclamation and closure costs | 86,045 | 85,580 | $ 95,538 | $ 57,250
Reclamation and closure costs, current | (6,679) | (5,653) |  |
Reclamation and closure costs, long-term | 79,366 | 79,927 |  |
Operating Properties [Member] | Greens Creek [Member] |  |  |  |
Operating properties: |  |  |  |
Reclamation and closure costs | 41,677 | 39,014 |  |
Non-operating properties: |  |  |  |
Reclamation and closure costs | 41,677 | 39,014 |  |
Operating Properties [Member] | Lucky Friday [Member] |  |  |  |
Operating properties: |  |  |  |
Reclamation and closure costs | 9,911 | 9,194 |  |
Non-operating properties: |  |  |  |
Reclamation and closure costs | 9,911 | 9,194 |  |
Operating Properties [Member] | Casa Berardi [Member] |  |  |  |
Operating properties: |  |  |  |
Reclamation and closure costs | 6,729 | 5,475 |  |
Non-operating properties: |  |  |  |
Reclamation and closure costs | 6,729 | 5,475 |  |
Operating Properties [Member] | San Sebastian [Member] |  |  |  |
Operating properties: |  |  |  |
Reclamation and closure costs | 5,067 | 5,592 |  |
Non-operating properties: |  |  |  |
Reclamation and closure costs | 5,067 | 5,592 |  |
Non-Operating Properties [Member] | Troy Mine [Member] |  |  |  |
Operating properties: |  |  |  |
Reclamation and closure costs | 12,724 | 16,167 |  |
Non-operating properties: |  |  |  |
Reclamation and closure costs | 12,724 | 16,167 |  |
Non-Operating Properties [Member] | Johnny M Mine Area near San Mateo, New Mexico [Member] |  |  |  |
Operating properties: |  |  |  |
Reclamation and closure costs | 5,813 | 5,830 |  |
Non-operating properties: |  |  |  |
Reclamation and closure costs | 5,813 | 5,830 |  |
Non-Operating Properties [Member] | Republic [Member] |  |  |  |
Operating properties: |  |  |  |
Reclamation and closure costs | 1,500 | 1,500 |  |
Non-operating properties: |  |  |  |
Reclamation and closure costs | 1,500 | 1,500 |  |
Non-Operating Properties [Member] | All Other Sites [Member] |  |  |  |
Operating properties: |  |  |  |
Reclamation and closure costs | 2,624 | 2,808 |  |
Non-operating properties: |  |  |  |
Reclamation and closure costs | $ 2,624 | $ 2,808 |  |

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- Definition Accrued reclamation and closure costs total. + References No definition available. + Details
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- Definition Current portion of reclamation reserve to restore a mining or drilling site to the condition agreed upon within the mining or drilling contract. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6911-107765 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of a reclamation and mine closing liability that is associated with a legal obligation for the closure and reclamation of a mine including the removal of buildings, equipment, machinery and other physical remnants of mining, closure of tailings impoundments, leach pads and other mine features, and contouring, covering and revegetation of waste rock piles and other disturbed areas. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 5.Y.Q2) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 + Details
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