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Use of Estimates, Assumptions and Judgements (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2019 $ / T $ / oz
Gold Commodity Type [member] |
Disclosure Of Detailed Information About Use Of Judgements And Estimates Explanatory [line items] |
Long term prices used for reserves and resource estimates related to commodity | $ / oz | 1,380
Silver Commodity Type [member] |
Disclosure Of Detailed Information About Use Of Judgements And Estimates Explanatory [line items] |
Long term prices used for reserves and resource estimates related to commodity | $ / oz | 17.00
Lead Commodity [member] |
Disclosure Of Detailed Information About Use Of Judgements And Estimates Explanatory [line items] |
Long term prices used for reserves and resource estimates related to commodity | $ / T | 2,170.00
Zinc Commodity [member] |
Disclosure Of Detailed Information About Use Of Judgements And Estimates Explanatory [line items] |
Long term prices used for reserves and resource estimates related to commodity | $ / T | 2,590

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