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Financial Instruments and Risk Management (Contractual Commitments) (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
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Disclosure of detailed information about financial instruments [abstract] |  |
Operating and financing leases, less than 1 year | $ 0.5 |
Operating and financing leases, 2-3 years | 0.9 |
Operating and financing leases, 4-5 years | 0.2 |
Operating and financing leases, more than 5 years | 0.0 |
Operating and financing leases, total | 1.6 |
Accounts payable and accrued liabilities, less than 1 year | 181.2 | $ 157.4
Accounts payable and accrued liabilities, 2-3 years | 0.0 |
Accounts payable and accrued liabilities, 4-5 years | 0.0 |
Accounts payable and accrued liabilities, more than 5 years | 0.0 |
Accounts payable and accrued liabilities, total | 181.2 |
Decommissioning liability, less than 1 year | 8.5 |
Decommissioning liability, 2-3 years | 43.3 |
Decommissioning liability, 4-5 years | 12.0 |
Decommissioning liability, more than 5 years | 70.2 |
Decommissioning liability, total | 134.0 | $ 114.9
Contract mining, less than 1 year | 43.0 |
Contract mining, 2-3 years | 52.4 |
Contract mining, 4-5 years | 30.1 |
Contract mining, more than 5 years | 0.0 |
Contract mining, total | 125.5 |
Capital commitments, less than 1 year | 124.8 |
Capital commitments, 2-3 years | 30.6 |
Capital commitments, 4-5 years | 0.0 |
Capital commitments, more than 5 years | 0.0 |
Capital commitments, total | 155.4 |
Contractual obligation, less than 1 year | 358.0 |
Contractual obligation, 2-3 years | 127.2 |
Contractual obligation, 4-5 years | 42.3 |
Contractual obligation, more than 5 years | 70.2 |
Contractual obligation, total | $ 597.7 |

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- Definition Capital Commitments, Future Minimum Payments Due, Next Twelve Months + References No definition available. + Details
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- Definition Capital Commitments, Future Minimum Payments Due Thereafter + References No definition available. + Details
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- Definition Capital Commitments, Future Minimum Payments Due in Four and Five Years + References No definition available. + Details
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- Definition Contract Mining + References No definition available. + Details
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- Definition Contractual Obligation, Due after Fifth Year + References No definition available. + Details
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- Definition Contractual Obligation, Due in Fourth and Fifth Year + References No definition available. + Details
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- Definition Contractual Obligation, Future Minimum Payments Due, Remainder of Fiscal Year + References No definition available. + Details
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- Definition Longterm Provision For Decommissioning Restoration And Rehabilitation Costs, Maturities, Repayments of Principal after Year Five + References No definition available. + Details
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- Definition Longterm Provision For Decommissioning Restoration And Rehabilitation Costs, Repayments of Principal in Next Twelve Months + References No definition available. + Details
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- Definition Operating and Financing Leases, Future Minimum Payments Due + References No definition available. + Details
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- Definition Operating and Financing Leases, Future Minimum Payments Due, Next Twelve Months + References No definition available. + Details
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- Definition Operating and Financing Leases, Future Minimum Payments, Due Thereafter + References No definition available. + Details
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- Definition Operating and Financing Leases, Future Minimum Payments, Due in Four and Five Years + References No definition available. + Details
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- Definition Operating and Financing Leases, Future Minimum Payments, Due in Two and Three Years + References No definition available. + Details
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