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Inventory (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Disclosure of inventories [Line Items] |  |  |
Mining and processing costs, inventories |  | $ 400.5 | $ 360.4
Amortization |  | 171.5 | 170.9
Amortization costs, Inventories |  |  | 170.9
Inventory net realizable value adjustment (note 6) | $ 33.9 | 33.9 | $ 0.0
Inventory write-down, after tax |  | 22.4 |
Mining and Processing Costs |  |  |
Disclosure of inventories [Line Items] |  |  |
Inventory net realizable value adjustment (note 6) |  | 27.6 |
Amortization |  |  |
Disclosure of inventories [Line Items] |  |  |
Inventory net realizable value adjustment (note 6) |  | $ 6.3 |

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- Definition The amount of expense recognised related to the write-down of inventories to net realisable value. [Refer: Inventories] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 2 -IssueDate 2022-03-24 -Paragraph 36 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=2&code=ifrs-tx-2022-en-r&anchor=para_36_e&doctype=Standard -URIDate 2022-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2022-03-24 -Paragraph 98 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_98_a&doctype=Standard -URIDate 2022-03-24 + Details
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