XML 84 R50.htm IDEA: XBRL DOCUMENT
v3.24.1

Mineral Property, Plant and Equipment (Narrative) (Details) $ in Millions |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
May 23, 2023 USD ($) shares | May 23, 2023 USD ($) $ / shares shares | Feb. 28, 2022 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Disclosure of detailed information about property, plant and equipment [line items] |  |  |  |  |  |
Construction in progress |  |  |  | $ 299.0 | $ 155.8 |
Cash and cash equivalents |  |  |  | 224.8 | 129.8 | $ 172.5
Total financial instrument exposure to credit risk |  |  |  | 242.6 | 153.5 |
Milestone payments |  |  |  | 5.7 | 19.1 |
Concentrate Receivable |  |  |  |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |  |  |  |
Milestone payments |  |  |  |  | $ 19.1 |
Esperanza Project |  |  |  |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |  |  |  |
Proceeds from disposal of non-current assets or disposal groups classified as held for sale and discontinued operations |  |  | $ 60.0 |  |  |
Cash and cash equivalents |  |  | $ 5.0 |  |  |
Manitou Gold Inc. |  |  |  |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |  |  |  |
Number of Alamos shares for each Manitou share held | shares | 0.0035251 | 0.0035251 |  |  |  |
Ownership interest (in shares) | shares | 65,211,077 | 65,211,077 |  |  |  |
Ownership interest, common stock (percentage) | 0.19 | 0.19 |  |  |  |
Common shares issued as part of consideration | shares | 984,760 | 984,760 |  |  |  |
Common shares as payment for control obligations | shares | 60,833 | 60,833 |  |  |  |
Share price (cad per share) | $ / shares |  | $ 17.37 |  |  |  |
Consideration transferred, acquisition-date fair value | $ 16.7 | $ 16.7 |  | 16.7 |  |
Transaction costs | $ 0.2 |  |  | $ 0.2 |  |

X
- Definition Business Acquisition, Consideration, Common Shares Issued + References No definition available. + Details
Name: | agi_BusinessAcquisitionConsiderationCommonSharesIssued
Namespace Prefix: | agi_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Business Acquisition, Number of Shares Issued For Each Share Held + References No definition available. + Details
Name: | agi_BusinessAcquisitionNumberOfSharesIssuedForEachShareHeld
Namespace Prefix: | agi_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Business Acquisition, Obligations, Common Shares Payment + References No definition available. + Details
Name: | agi_BusinessAcquisitionObligationsCommonSharesPayment
Namespace Prefix: | agi_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Milestone Payments And Cash From Percentage of Silver Produced + References No definition available. + Details
Name: | agi_MilestonePaymentsAndCashFromPercentageOfSilverProduced
Namespace Prefix: | agi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Ownership Interest, Percentage Of Common Stock + References No definition available. + Details
Name: | agi_OwnershipInterestPercentageOfCommonStock
Namespace Prefix: | agi_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | instant

X
- Definition Ownership Interest, Shares + References No definition available. + Details
Name: | agi_OwnershipInterestShares
Namespace Prefix: | agi_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Share Price1 + References No definition available. + Details
Name: | agi_SharePrice1
Namespace Prefix: | agi_
Data Type: | dtr-types1:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The fair value, at acquisition date, of the consideration transferred in a business combination. [Refer: Business combinations [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2023-01-01 -Paragraph B64 -Subparagraph f -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2023-en-r&anchor=para_B64_f&doctype=Appendix&subtype=B -URIDate 2023-03-23 + Details
Name: | ifrs-full_AcquisitiondateFairValueOfTotalConsiderationTransferred
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The amount of acquisition-related costs for transactions recognised separately from the acquisition of assets and the assumption of liabilities in business combinations. [Refer: Business combinations [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2023-01-01 -Paragraph B64 -Subparagraph m -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2023-en-r&anchor=para_B64_m&doctype=Appendix&subtype=B -URIDate 2023-03-23 + Details
Name: | ifrs-full_AcquisitionrelatedCostsForTransactionRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombination
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 7 -IssueDate 2023-01-01 -Paragraph 45 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2023-en-r&anchor=para_45&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2023-01-01 -Paragraph B13 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2023-en-r&anchor=para_B13_a&doctype=Appendix&subtype=B -URIDate 2023-03-23 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 54 -Subparagraph i -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_54_i&doctype=Standard -URIDate 2023-03-23 + Details
Name: | ifrs-full_CashAndCashEquivalents
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of expenditure capitalised during the construction of non-current assets that are not yet available for use. [Refer: Non-current assets] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 16 -IssueDate 2023-01-01 -Paragraph 37 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=16&code=ifrs-tx-2023-en-r&anchor=para_37&doctype=Standard -URIDate 2023-03-23 + Details
Name: | ifrs-full_ConstructionInProgress
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + References No definition available. + Details
Name: | ifrs-full_DisclosureOfPropertyPlantAndEquipmentLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount that best represents the maximum exposure to credit risk without taking into account any collateral held or other credit enhancements (for example, netting agreements that do not qualify for offset in accordance with IAS 32). [Refer: Credit risk [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2023-01-01 -Paragraph 35K -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_35K_a&doctype=Standard -URIDate 2023-03-23 + Details
Name: | ifrs-full_MaximumExposureToCreditRisk
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition The cash inflow from the disposal of non-current assets or disposal groups classified as held for sale and discontinued operations. [Refer: Discontinued operations [member]; Disposal groups classified as held for sale [member]; Non-current assets or disposal groups classified as held for sale] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 7 -IssueDate 2023-01-01 -Paragraph 16 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2023-en-r&anchor=para_16&doctype=Standard -URIDate 2023-03-23 + Details
Name: | ifrs-full_ProceedsFromDisposalOfNoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleAndDiscontinuedOperations
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=agi_ConcentrateReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | agi_ProjectNameAxis=agi_EsperanzaProjectMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_BusinessCombinationsAxis=agi_ManitouGoldIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |