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v3.19.1

Financial Instruments and Risk Management (Contractual Commitments) (Details) $ in Millions | Dec. 31, 2018 USD ($)
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Disclosure of detailed information about financial instruments [abstract] |
Operating and financing leases, less than 1 year | $ 3.1
Operating and financing leases, 2-3 years | 1.5
Operating and financing leases, 4-5 years | 0.7
Operating and financing leases, more than 5 years | 0.6
Operating and financing leases, total | 5.9
Accounts payable and accrued liabilities, less than 1 year | 118.7
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 | 118.7
Decommissioning liability, less than 1 year | 0.0
Decommissioning liability, 2-3 years | 6.4
Decommissioning liability, 4-5 years | 0.0
Decommissioning liability, more than 5 years | 47.0
Decommissioning liability, total | 53.4
Contract mining, less than 1 year | 31.9
Contract mining, 2-3 years | 32.0
Contract mining, 4-5 years | 0.0
Contract mining, more than 5 years | 0.0
Contract mining, total | 63.9
Capital commitments, less than 1 year | 24.5
Capital commitments, 2-3 years | 0.0
Capital commitments, 4-5 years | 0.0
Capital commitments, more than 5 years | 0.0
Capital commitments, total | 24.5
Contractual obligation, less than 1 year | 178.2
Contractual obligation, 2-3 years | 39.9
Contractual obligation, 4-5 years | 0.7
Contractual obligation, more than 5 years | 47.6
Contractual obligation, total | $ 266.4

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