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v3.19.3.a.u2

Mineral Property, Pland and Equipment (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2019
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | $ 2,813.3 |  |
Mineral property, plant and equipment | 2,813.3 |  | $ 2,933.4
Gross carrying amount [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 3,846.4 | $ 3,628.7 |
Additions | 277.8 | 226.5 |
Transfers | 13.3 | 0.0 |
Right-of-use assets (note 16) | (2.4) |  |
Disposals | (1.9) | (8.8) |
Mineral property, plant and equipment | 3,846.4 | 3,628.7 | 4,138.0
Accumulated depreciation, amortisation and impairment [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 1,033.1 | 875.3 |
Amortization | 172.7 | 160.5 |
Disposals | (1.2) | (2.7) |
Mineral property, plant and equipment | 1,033.1 | 875.3 | 1,204.6
Plant and Equipment [Member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 796.5 |  |
Mineral property, plant and equipment | 796.5 |  | 856.8
Plant and Equipment [Member] | Gross carrying amount [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 1,200.1 | 1,103.0 |
Additions | 126.9 | 105.9 |
Transfers | 0.0 | 0.0 |
Right-of-use assets (note 16) | (2.4) |  |
Disposals | (1.9) | (8.8) |
Mineral property, plant and equipment | 1,200.1 | 1,103.0 | 1,327.5
Plant and Equipment [Member] | Accumulated depreciation, amortisation and impairment [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 403.6 | 333.9 |
Amortization | 68.3 | 72.4 |
Disposals | (1.2) | (2.7) |
Mineral property, plant and equipment | 403.6 | 333.9 | 470.7
Mineral Property - Depletable [Member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 1,681.6 |  |
Mineral property, plant and equipment | 1,681.6 |  | 1,720.7
Mineral Property - Depletable [Member] | Gross carrying amount [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 2,299.7 | 2,118.3 |
Additions | 130.2 | 90.7 |
Transfers | 13.3 | 90.7 |
Right-of-use assets (note 16) | 0.0 |  |
Disposals | 0.0 | 0.0 |
Mineral property, plant and equipment | 2,299.7 | 2,118.3 | 2,443.2
Mineral Property - Depletable [Member] | Accumulated depreciation, amortisation and impairment [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 618.1 | 530.0 |
Amortization | 104.4 | 88.1 |
Disposals | 0.0 | 0.0 |
Mineral property, plant and equipment | 618.1 | 530.0 | 722.5
Mineral Property - Non-Depletable [Member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 90.7 |  |
Mineral property, plant and equipment | 90.7 |  | 99.8
Mineral Property - Non-Depletable [Member] | Gross carrying amount [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 95.8 | 80.5 |
Additions | 9.1 | 15.3 |
Transfers | 0.0 | 0.0 |
Right-of-use assets (note 16) | 0.0 |  |
Disposals | 0.0 | 0.0 |
Mineral property, plant and equipment | 95.8 | 80.5 | 104.9
Mineral Property - Non-Depletable [Member] | Accumulated depreciation, amortisation and impairment [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 5.1 | 5.1 |
Amortization | 0.0 | 0.0 |
Disposals | 0.0 | 0.0 |
Mineral property, plant and equipment | 5.1 | 5.1 | 5.1
Exploration and evaluation assets [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 244.5 |  |
Mineral property, plant and equipment | 244.5 |  | 256.1
Exploration and evaluation assets [member] | Gross carrying amount [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 250.8 | 326.9 |
Additions | 11.6 | 14.6 |
Transfers | 0.0 | (90.7) |
Right-of-use assets (note 16) | 0.0 |  |
Disposals | 0.0 | 0.0 |
Mineral property, plant and equipment | 250.8 | 326.9 | 262.4
Exploration and evaluation assets [member] | Accumulated depreciation, amortisation and impairment [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 6.3 | 6.3 |
Amortization | 0.0 | 0.0 |
Disposals | 0.0 | 0.0 |
Mineral property, plant and equipment | $ 6.3 | $ 6.3 | $ 6.3

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