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v3.20.2

Note 4 - Commitments, Contingencies and Obligations (Details Textual) $ in Thousands, $ in Millions |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 09, 2020 CAD ($) | Sep. 09, 2020 CAD ($) | Aug. 09, 2020 CAD ($) | Jul. 09, 2020 CAD ($) | Oct. 30, 2019 USD ($) | Oct. 31, 2019 USD ($) | Jul. 31, 2018 USD ($) | Dec. 31, 2014 USD ($) | Aug. 31, 2012 USD ($) | Jun. 30, 2011 USD ($) | Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Dec. 31, 2014 USD ($) | Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Jul. 09, 2020 USD ($) | Jul. 09, 2020 CAD ($) | Feb. 19, 2020 USD ($) | Dec. 31, 2019 USD ($) | Sep. 11, 2018
Environmental Remediation Expense |  |  |  |  |  | $ 6,100 |  |  |  |  | $ 1,254 | $ 1,907 |  | $ 2,807 | $ 3,529 |  |  |  |  |
Payments of Debt Issuance Costs |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,287 | $ 587 |  |  |  |  |
Contractual Obligation, Total |  |  |  |  |  |  |  |  |  |  | 700 |  |  | 700 |  |  |  |  |  |
Finance Lease, Liability, Payment, Due, Total |  |  |  |  |  |  |  |  |  |  | 14,989 |  |  | 14,989 |  |  |  |  |  |
Lessee, Operating Lease, Liability, to be Paid, Total |  |  |  |  |  |  |  |  |  |  | 13,602 |  |  | 13,602 |  |  |  |  |  |
Letters of Credit Outstanding, Amount |  |  |  |  |  |  |  |  |  |  | 20,300 |  |  | 20,300 |  |  |  |  |  |
Performance Obligation Commitments [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Surety Bonds |  |  |  |  |  |  |  |  |  |  | 182,600 |  |  | 182,600 |  |  |  |  |  |
Letters of Credit Outstanding, Amount |  |  |  |  |  |  |  |  |  |  | 20,300 |  |  | 20,300 |  |  |  |  |  |
Lucky Friday [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Open Purchase Orders |  |  |  |  |  |  |  |  |  |  | 3,200 |  |  | 3,200 |  |  |  |  |  |
Casa Berardi [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Open Purchase Orders |  |  |  |  |  |  |  |  |  |  | 400 |  |  | 400 |  |  |  |  |  |
Greens Creek [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Open Purchase Orders |  |  |  |  |  |  |  |  |  |  | 5,600 |  |  | 5,600 |  |  |  |  |  |
Nevada Operations [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Open Purchase Orders |  |  |  |  |  |  |  |  |  |  | 3,300 |  |  | 3,300 |  |  |  |  |  |
Senior Notes [Member] | The 2028 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 475,000 |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7.25% |  |
Long-term Debt, Gross |  |  |  |  |  |  |  |  |  |  | $ 475,000 |  |  | $ 475,000 |  |  |  |  |  |
Senior Notes [Member] | The 2021 Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6.875% |
Long-term Debt, Gross |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 506,500 |
Senior Notes [Member] | The IQ Notes [Member]] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 36,800 | $ 50.0 |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 6.515% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Number of Issuance Installments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4 | 4 |  |  |
Proceeds from Issuance of Debt |  | $ 12.5 | $ 12.5 | $ 12.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments of Debt Issuance Costs |  | $ 0.6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Member] | The IQ Notes [Member]] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Debt | $ 12.5 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Canadian Assets of Klondex [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 13.00%
PRP Lawsuit in Mineral County, Colorado [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingency, Damages Sought, Value |  |  |  |  | $ 5,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lawsuit filed in Ontario (Canada) Superior Court of Justice [Member] | Waterton Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right, Issued During Period, Value |  |  |  |  |  |  | $ 3,700 |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right, Warrants Entitled, Value |  |  |  |  |  |  | 8,900 |  |  |  |  |  |  |  |  |  |  |  |  |
Johnny M Mine Area near San Mateo, New Mexico [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payment Of Response Costs |  |  |  |  |  |  |  | $ 1,100 | $ 1,100 |  |  |  |  |  |  |  |  |  |  |
Estimated Response Costs |  |  |  |  |  |  | $ 9,600 | 6,100 |  |  |  |  |  |  |  |  |  |  |  |
Environmental Remediation Expense |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,600 |  |  |  |  |  |  |
Johnny M Mine Area near San Mateo, New Mexico [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated Alternative Response Costs |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |
Johnny M Mine Area near San Mateo, New Mexico [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated Alternative Response Costs |  |  |  |  |  |  |  | $ 221,000 |  |  |  |  |  |  |  |  |  |  |  |
Carpenter Snow Creek Superfund Site, Cascade County, Montana [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated Response Costs |  |  |  |  |  |  |  |  |  | $ 4,500 |  |  |  |  |  |  |  |  |  |
Estimated Future Response Cost |  |  |  |  |  |  |  |  |  | $ 100,000 |  |  |  |  |  |  |  |  |  |

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