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Mineral Property, Plant and Equipment (Net Value Carrying Values) (Details) $ in Millions | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2020 CAD ($)
--- | --- | --- | ---
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | $ 3,108.5 | $ 3,101.3 |
Plant and Equipment [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 911.5 | 888.7 |
Mineral property - non-depletable |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 1,819.4 | 1,768.2 |
Mineral Property - Non-Depletable [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 143.2 | 157.7 |
Exploration and evaluation |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 234.4 | 286.7 |
Operating segments [member] | Young-Davidson [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 1,520.6 | 1,507.5 |
Operating segments [member] | Young-Davidson [Member] | Plant and Equipment [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 686.8 | 684.7 |
Operating segments [member] | Young-Davidson [Member] | Mineral property - non-depletable |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 833.8 | 822.8 |
Operating segments [member] | Young-Davidson [Member] | Mineral Property - Non-Depletable [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 0.0 | 0.0 |
Operating segments [member] | Young-Davidson [Member] | Exploration and evaluation |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 0.0 | 0.0 |
Operating segments [member] | Island Gold [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 1,016.0 | 912.0 |
Operating segments [member] | Island Gold [Member] | Plant and Equipment [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 115.4 | 88.4 |
Operating segments [member] | Island Gold [Member] | Mineral property - non-depletable |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 876.4 | 818.7 |
Operating segments [member] | Island Gold [Member] | Mineral Property - Non-Depletable [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 24.2 | 4.9 |
Operating segments [member] | Island Gold [Member] | Exploration and evaluation |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 0.0 | 0.0 |
Operating segments [member] | Mulatos [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 334.3 | 246.5 |
Operating segments [member] | Mulatos [Member] | Plant and Equipment [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 106.1 | 107.8 |
Operating segments [member] | Mulatos [Member] | Mineral property - non-depletable |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 109.2 | 126.7 |
Operating segments [member] | Mulatos [Member] | Mineral Property - Non-Depletable [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 119.0 | 12.0 |
Operating segments [member] | Mulatos [Member] | Exploration and evaluation |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 0.0 | 0.0 |
Operating segments [member] | Kirazli Segment [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment |  |  | $ 141,100,000
Operating segments [member] | Kirazli Segment [Member] | Plant and Equipment [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment |  |  | 300,000
Operating segments [member] | Kirazli Segment [Member] | Mineral Property - Non-Depletable [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment |  |  | $ 140,800,000
Corporate and other [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 237.6 | 294.2 |
Corporate and other [Member] | Plant and Equipment [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 3.2 | 7.5 |
Corporate and other [Member] | Mineral property - non-depletable |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 0.0 | 0.0 |
Corporate and other [Member] | Mineral Property - Non-Depletable [Member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | 0.0 | 0.0 |
Corporate and other [Member] | Exploration and evaluation |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Mineral property, plant and equipment | $ 234.4 | $ 286.7 |

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- Definition The amount of tangible assets that: (a) are held for use in the production or supply of goods or services, for rental to others, or for administrative purposes; and (b) are expected to be used during more than one period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2021-01-01 -Paragraph 73 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2021-en-r&anchor=para_73_e&doctype=Standard -URIDate 2021-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 54 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_54_a&doctype=Standard -URIDate 2021-03-24 + Details
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