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Mineral Property, Plant and Equipment (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | $ 3,360.1 |
Reversal of impairment (Note 9) | (57.1) | $ 0.0
Mineral property, plant and equipment | 4,618.0 | 3,360.1
Cost |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | 5,468.5 | 5,110.2
Additions | 420.4 | 367.9
Transfer of La Yaqui Grande Assets |  | 20.0
Revisions | 0.0 | 0.0
Disposals | (23.9) | (38.2)
Mineral property, plant and equipment | 6,879.2 | 5,468.5
Cost | Lake Lynn Assets |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Revisions | 0.0 |
Accumulated amortization and impairment |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | (2,108.4) | (1,936.4)
Amortization | (222.2) | (207.6)
Disposals | 13.3 | 35.6
Reversal of impairment (Note 9) | (56.1) |
Mineral property, plant and equipment | (2,261.2) | (2,108.4)
Right of Use Assets |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Revisions | 2.6 | 8.6
Plant and equipment(v) |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | 928.2 |
Mineral property, plant and equipment | 1,629.5 | 928.2
Plant and equipment(v) | Cost |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | 1,808.4 | 1,788.4
Additions | 83.2 | 51.5
Transfer of La Yaqui Grande Assets |  | 0.0
Revisions | 39.1 | 4.0
Disposals | (23.9) | (35.5)
Mineral property, plant and equipment | 2,597.5 | 1,808.4
Plant and equipment(v) | Cost | Lake Lynn Assets |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Revisions | 0.0 |
Plant and equipment(v) | Accumulated amortization and impairment |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | (880.2) | (807.9)
Amortization | (122.9) | (106.6)
Disposals | 13.3 | 34.3
Reversal of impairment (Note 9) | (21.8) |
Mineral property, plant and equipment | (968.0) | (880.2)
Plant and equipment(v) | Right of Use Assets |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Revisions | 7.5 | 0.0
Mineral Property |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | 2,214.2 |
Mineral property, plant and equipment | 2,892.0 | 2,214.2
Mineral Property | Cost |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | 3,357.5 | 3,070.0
Additions | 303.8 | 284.2
Transfer of La Yaqui Grande Assets |  | 0.0
Revisions | (39.1) | (4.0)
Disposals | 0.0 | (1.3)
Mineral property, plant and equipment | 4,100.3 | 3,357.5
Mineral Property | Cost | Lake Lynn Assets |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Revisions | 175.7 |
Mineral Property | Accumulated amortization and impairment |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | (1,143.3) | (1,043.6)
Amortization | (99.3) | (101.0)
Disposals | 0.0 | 1.3
Reversal of impairment (Note 9) | (34.3) |
Mineral property, plant and equipment | (1,208.3) | (1,143.3)
Mineral Property | Right of Use Assets |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Revisions | (4.9) | 8.6
Exploration and evaluation |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | 217.7 |
Mineral property, plant and equipment | 96.5 | 217.7
Exploration and evaluation | Cost |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | 302.6 | 251.8
Additions | 33.4 | 32.2
Transfer of La Yaqui Grande Assets |  | 20.0
Revisions | 0.0 | 0.0
Disposals | 0.0 | (1.4)
Mineral property, plant and equipment | 181.4 | 302.6
Exploration and evaluation | Cost | Lake Lynn Assets |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Revisions | (175.7) |
Exploration and evaluation | Accumulated amortization and impairment |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | (84.9) | (84.9)
Amortization | 0.0 | 0.0
Disposals | 0.0 | 0.0
Reversal of impairment (Note 9) | 0.0 |
Mineral property, plant and equipment | (84.9) | (84.9)
Exploration and evaluation | Right of Use Assets |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Revisions | 0.0 | 0.0
Mineral Property, Plant and Equipment |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Property, plant and equipment | 3,360.1 |
Mineral property, plant and equipment | 4,618.0 | $ 3,360.1
Manitou Gold Inc. | Cost |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Additions | 21.1 |
Manitou Gold Inc. | Plant and equipment(v) | Cost |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Additions | 0.0 |
Manitou Gold Inc. | Mineral Property | Cost |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Additions | 0.0 |
Manitou Gold Inc. | Exploration and evaluation | Cost |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Additions | 21.1 |
Argonaut Transaction |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Mineral property, plant and equipment | 683.2 |
Argonaut Transaction | Cost |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Additions | 990.5 |
Argonaut Transaction | Exploration and evaluation | Cost |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Additions | 0.0 |
Argonaut Transaction | Mineral Property, Plant and Equipment |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |
Mineral property, plant and equipment | $ 307.3 |

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- Definition The amount of additions to property, plant and equipment other than those acquired through business combinations. [Refer: Total for all business combinations [member]; Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2024-01-01 -Paragraph 73 -Subparagraph e -Clause i -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=16&code=ifrs-tx-2024-en-r&anchor=para_73_e_i&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of depreciation of property, plant and equipment. [Refer: Depreciation and amortisation expense; Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2024-01-01 -Paragraph 73 -Subparagraph e -Clause vii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=16&code=ifrs-tx-2024-en-r&anchor=para_73_e_vii&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2024-01-01 -Paragraph 75 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=16&code=ifrs-tx-2024-en-r&anchor=para_75_a&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The increase (decrease) in property, plant and equipment resulting from changes that the entity does not separately disclose in the same statement or note. [Refer: Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2024-01-01 -Paragraph 73 -Subparagraph e -Clause ix -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=16&code=ifrs-tx-2024-en-r&anchor=para_73_e_ix&doctype=Standard -URIDate 2024-03-27 + Details
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