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Decommissioning Liabilities (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Reconciliation of changes in other provisions [abstract] |  |
Reclamation expenses | $ 1.2 | $ 3.5
Less: Current portion of decommissioning liability 1 | (3.3) |
Provision for decommissioning, restoration and rehabilitation costs [member] |  |
Reconciliation of changes in other provisions [abstract] |  |
Beginning balance | 75.2 | 59.0
Reclamation expenditures |  | (3.5)
Accretion expense | 2.3 | 2.6
Reclamation expenses | 1.2 |
Revisions to expected discounted cash flows | 29.8 | 17.1
Less: Current portion of decommissioning liability 1 | (3.3) |
Other non-current provisions | 102.8 |
Ending balance | $ 106.1 | $ 75.2

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- Definition The increase (decrease) in other provisions resulting from a change in discount rate. [Refer: Other provisions] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 37 -IssueDate 2021-01-01 -Paragraph 84 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=37&code=ifrs-tx-2021-en-r&anchor=para_84_e&doctype=Standard -URIDate 2021-03-24 + Details
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