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v3.19.1

Mineral Property, Pland and Equipment (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2018
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | $ 2,753.4 |  |
Mineral property, plant and equipment | 2,753.4 |  | $ 2,813.3
Gross carrying amount [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 3,628.7 | $ 2,678.1 |
Additions | 226.5 | 179.0 |
Acquisitions of new entities |  | 774.3 |
Transfers | 0.0 |  |
Disposals | (8.8) | (2.7) |
Mineral property, plant and equipment | 3,628.7 | 2,678.1 | 3,846.4
Accumulated depreciation, amortisation and impairment [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 875.3 | 759.9 |
Amortization | 160.5 | 116.5 |
Disposals | (2.7) | (1.1) |
Mineral property, plant and equipment | 875.3 | 759.9 | 1,033.1
Plant and Equipment [Member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 769.1 |  |
Mineral property, plant and equipment | 769.1 |  | 814.0
Plant and Equipment [Member] | Gross carrying amount [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 1,103.0 | 983.6 |
Additions | 123.4 | 66.4 |
Acquisitions of new entities |  | 55.7 |
Transfers | 0.0 |  |
Disposals | (8.8) | (2.7) |
Mineral property, plant and equipment | 1,103.0 | 983.6 | 1,217.6
Plant and Equipment [Member] | Accumulated depreciation, amortisation and impairment [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 333.9 | 273.4 |
Amortization | 72.4 | 61.6 |
Disposals | (2.7) | (1.1) |
Mineral property, plant and equipment | 333.9 | 273.4 | 403.6
Mineral Property - Depletable [Member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 1,588.3 |  |
Mineral property, plant and equipment | 1,588.3 |  | 1,672.2
Mineral Property - Depletable [Member] | Gross carrying amount [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 2,118.3 | 1,343.0 |
Additions | 73.4 | 56.7 |
Acquisitions of new entities |  | 718.6 |
Transfers | 98.6 |  |
Disposals | 0.0 | 0.0 |
Mineral property, plant and equipment | 2,118.3 | 1,343.0 | 2,290.3
Mineral Property - Depletable [Member] | Accumulated depreciation, amortisation and impairment [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 530.0 | 475.1 |
Amortization | 88.1 | 54.9 |
Disposals | 0.0 | 0.0 |
Mineral property, plant and equipment | 530.0 | 475.1 | 618.1
Mineral Property - Non-Depletable [Member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 75.4 |  |
Mineral property, plant and equipment | 75.4 |  | 90.7
Mineral Property - Non-Depletable [Member] | Gross carrying amount [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 80.5 | 66.2 |
Additions | 15.3 | 14.3 |
Acquisitions of new entities |  | 0.0 |
Transfers | 0.0 |  |
Disposals | 0.0 | 0.0 |
Mineral property, plant and equipment | 80.5 | 66.2 | 95.8
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 | 320.6 |  |
Mineral property, plant and equipment | 320.6 |  | 236.4
Exploration and evaluation assets [member] | Gross carrying amount [member] |  |  |
Reconciliation of changes in property, plant and equipment [abstract] |  |  |
Property, plant and equipment | 326.9 | 285.3 |
Additions | 14.4 | 41.6 |
Acquisitions of new entities |  | 0.0 |
Transfers | (98.6) |  |
Disposals | 0.0 | 0.0 |
Mineral property, plant and equipment | 326.9 | 285.3 | 242.7
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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