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Mineral Property, Plant and Equipment (Net Value Carrying Values) (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
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Disclosure of detailed information about property, plant and equipment [line items] |  |
Property, plant and equipment | $ 3,360.1 | $ 3,173.8
Mineral Property, Plant and Equipment |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Property, plant and equipment | 3,360.1 | 3,173.8
Capital Additions |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Property, plant and equipment | 367.9 | 329.8
Corporate and other | Mineral Property, Plant and Equipment |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Property, plant and equipment | 169.1 | 150.7
Corporate and other | Capital Additions |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Property, plant and equipment | 21.1 | 17.5
Operating segments | Young-Davidson | Mineral Property, Plant and Equipment |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Property, plant and equipment | 1,500.3 | 1,504.7
Operating segments | Young-Davidson | Capital Additions |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Property, plant and equipment | 73.5 | 68.4
Operating segments | Island Gold | Mineral Property, Plant and Equipment |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Property, plant and equipment | 1,397.7 | 1,174.6
Operating segments | Island Gold | Capital Additions |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Property, plant and equipment | 243.4 | 185.1
Operating segments | Mulatos1 | Mineral Property, Plant and Equipment |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Property, plant and equipment | 293.0 | 343.8
Operating segments | Mulatos1 | Capital Additions |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |
Property, plant and equipment | $ 29.9 | $ 58.8

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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. Note that right-of-use assets are not included. [Contrast: Property, plant and equipment including right-of-use assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2023-01-01 -Paragraph 73 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=16&code=ifrs-tx-2023-en-r&anchor=para_73_e&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 54 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_54_a&doctype=Standard -URIDate 2023-03-23 + Details
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