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Financial Instruments and Risk Management (Derivative Instrument Not Designated as Cash Flow Hedged Narrative) (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2023 USD ($) $ / oz oz | Dec. 31, 2022 USD ($)
Disclosure of detailed information about hedged items [line items] |  |
Ounces Subject to Contract | oz | 69,750 |
Unrealized gain on non-hedging derivatives | $ (0.9) | $ (0.3)
Expense relating to variable lease payments not included in measurement of lease liabilities | 104.2 | 88.2
Derivatives | Gold Options |  |
Disclosure of detailed information about hedged items [line items] |  |
Financial liabilities, at fair value | (0.8) |
Gold Options | Commodity price risk |  |
Disclosure of detailed information about hedged items [line items] |  |
Financial assets, at fair value |  | 0.1
Gains (losses) on change in fair value of derivatives | 0.1 | 3.5
Unrealized gain on non-hedging derivatives | $ 0.9 | $ 0.3
Purchase Put Options | Gold Options | 2024 | Commodity price risk |  |
Disclosure of detailed information about hedged items [line items] |  |
Average realized price per ounce | $ / oz | 1,926 |
Sold Call Option | Gold Options | 2024 | Commodity price risk |  |
Disclosure of detailed information about hedged items [line items] |  |
Average realized price per ounce | $ / oz | 2,356 |

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- Definition The amount of the expense relating to variable lease payments not included in the measurement of lease liabilities. Variable lease payments are the portion of payments made by a lessee to a lessor for the right to use an underlying asset during the lease term that varies because of changes in facts or circumstances occurring after the commencement date, other than the passage of time. [Refer: Lease liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 16 -IssueDate 2023-01-01 -Paragraph 53 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2023-en-r&anchor=para_53_e&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The fair value of financial assets. [Refer: At fair value [member]; Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2023-01-01 -Paragraph 25 -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_25&doctype=Standard -URIDate 2023-03-23 + Details
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