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Mineral Property, Plant and Equipment (Net Value Carrying Values) (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | $ 3,173.8 | $ 3,108.5
Plant and equipment |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 980.5 | 911.5
Depletable |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 1,899.5 | 1,819.4
Non-depletable |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 126.9 | 143.2
Exploration and evaluation |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 166.9 | 234.4
Corporate and other |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 150.7 | 217.8
Corporate and other | Plant and equipment |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 3.6 | 3.2
Corporate and other | Depletable |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Corporate and other | 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 | Exploration and evaluation |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 147.1 | 214.6
Operating segments | Young-Davidson |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 1,504.7 | 1,520.6
Operating segments | Young-Davidson | Plant and equipment |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 663.2 | 686.8
Operating segments | Young-Davidson | Depletable |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 841.5 | 833.8
Operating segments | Young-Davidson | Non-depletable |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 0.0 | 0.0
Operating segments | Young-Davidson | 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 | Island Gold |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 1,174.6 | 1,035.8
Operating segments | Island Gold | Plant and equipment |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 114.5 | 115.4
Operating segments | Island Gold | Depletable |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 939.8 | 876.4
Operating segments | Island Gold | Non-depletable |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 100.5 | 24.2
Operating segments | Island Gold | Exploration and evaluation |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 19.8 | 19.8
Operating segments | Mulatos1 |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 343.8 | 334.3
Operating segments | Mulatos1 | Plant and equipment |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 199.2 | 106.1
Operating segments | Mulatos1 | Depletable |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 118.2 | 109.2
Operating segments | Mulatos1 | Non-depletable |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | 26.4 | 119.0
Operating segments | Mulatos1 | Exploration and evaluation |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Mineral property, plant and equipment | $ 0.0 | $ 0.0

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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + References No definition available. + Details
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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 2022-03-24 -Paragraph 73 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=16&code=ifrs-tx-2022-en-r&anchor=para_73_e&doctype=Standard -URIDate 2022-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2022-03-24 -Paragraph 54 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_54_a&doctype=Standard -URIDate 2022-03-24 + Details
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