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Note 4 - Environmental and Reclamation Activities (Details) - Accrued Reclamation and Closure Cost Liability Activity - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Note 4 - Environmental and Reclamation Activities (Details) - Accrued Reclamation and Closure Cost Liability Activity [Line Items] |  |  |
Balance | $ 57,250 | $ 105,191 | $ 113,215
Accruals for estimated costs | 17,018 | 9,952 | 2,250
Revision of estimated cash flows due to changes in reclamation plans | 4,112 | 675 |
Addition due to development and production at our San Sebastian unit | 1,189 |  |
Payment of reclamation obligations | (1,544) | (58,568) | (18,272)
Balance | 95,538 | $ 57,250 | 105,191
Casa Berardi [Member] |  |  |
Note 4 - Environmental and Reclamation Activities (Details) - Accrued Reclamation and Closure Cost Liability Activity [Line Items] |  |  |
|  |  | $ 7,998
Revett Mining Company Inc [Member] |  |  |
Note 4 - Environmental and Reclamation Activities (Details) - Accrued Reclamation and Closure Cost Liability Activity [Line Items] |  |  |
| $ 17,513 |  |

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