XML 107 R73.htm IDEA: XBRL DOCUMENT
v3.24.1

Supplemental Cash Flow Information (Other Non-cash Items) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022
Disclosure of cash flow statement [Line Items] |  |
Unrealized gain on non-hedging derivatives | $ (0.9) | $ (0.3)
Reduction of obligation to renounce flow-through exploration expenditures | 0.7 | 2.7
Employee contributions | 4.7 | 2.8
Adjustments for interest income | 7.8 | 1.9
Adjustments for increase (decrease) in insurance, reinsurance and investment contract liabilities | (2.1) | (2.1)
Distribution of share-based compensation | 15.8 | 8.5
Loss on disposal of assets | 1.9 | 0.7
Other | (0.4) | 2.8
Other adjustments for non-cash items | 12.7 | (6.7)
Revision to reclamation for closed sites | 3.3 | 0.0
Silver Stream |  |
Disclosure of cash flow statement [Line Items] |  |
Gain (loss) on fair value adjustment | 0.0 | 2.6
Milestone Payments |  |
Disclosure of cash flow statement [Line Items] |  |
Unrealized gain on non-hedging derivatives | (13.4) | (1.1)
Provision for decommissioning, restoration and rehabilitation costs [member] |  |
Disclosure of cash flow statement [Line Items] |  |
Reclamation expenses | $ 0.3 | $ 0.4

X
- Definition Disclosure of cash flow statement [Line Items] + References No definition available. + Details
Name: | agi_DisclosureOfCashFlowStatementLineItems
Namespace Prefix: | agi_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Distribution of Share Based Compensation + References No definition available. + Details
Name: | agi_DistributionOfShareBasedCompensation
Namespace Prefix: | agi_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Gain (loss) on fair value adjustment + References No definition available. + Details
Name: | agi_GainLossOnFairValueAdjustment
Namespace Prefix: | agi_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Reduction of Obligation to Renounce Flow Through Exploration Costs + References No definition available. + Details
Name: | agi_ReductionofObligationtoRenounceFlowThroughExplorationCosts
Namespace Prefix: | agi_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Unrealized Gain (Loss) on Derivatives1 + References No definition available. + Details
Name: | agi_UnrealizedGainLossonDerivatives1
Namespace Prefix: | agi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Adjustments for increase (decrease) in insurance, reinsurance and investment contract liabilities to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Investment contracts liabilities; Profit (loss)] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 7 -IssueDate 2023-01-01 -Paragraph 20 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2023-en-r&anchor=para_20&doctype=Standard -URIDate 2023-03-23 + Details
Name: | ifrs-full_AdjustmentsForIncreaseDecreaseInInsuranceReinsuranceAndInvestmentContractLiabilities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Adjustments for interest income expense to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Interest income; Profit (loss)] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 7 -IssueDate 2023-01-01 -Paragraph 20 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2023-en-r&anchor=para_20&doctype=Standard -URIDate 2023-03-23 + Details
Name: | ifrs-full_AdjustmentsForInterestIncome
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The amount of employee contributions to retirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 26 -IssueDate 2023-01-01 -Paragraph 35 -Subparagraph b -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=26&code=ifrs-tx-2023-en-r&anchor=para_35_b_ii&doctype=Standard -URIDate 2023-03-23 + Details
Name: | ifrs-full_EmployeeContributions
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The amount of expense relating to restructuring. Restructuring is a programme that is planned and controlled by management and materially changes either the scope of a business undertaken by an entity or the manner in which that business is conducted. Such programmes include: (a) the sale or termination of a line of business; (b) closure of business locations in a country or region or the relocation of activities from one country or region to another; (c) changes in management structure; and (d) fundamental reorganisations that have a material effect on the nature and focus of the entity's operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 98 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_98_b&doctype=Standard -URIDate 2023-03-23 + Details
Name: | ifrs-full_ExpenseOfRestructuringActivities
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The losses on disposals of non-current assets. [Refer: Non-current assets] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 112 -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_112_c&doctype=Standard -URIDate 2023-03-23 + Details
Name: | ifrs-full_LossesOnDisposalsOfNoncurrentAssets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Adjustments for non-cash items to reconcile profit (loss) to net cash flow from (used in) operating activities that the entity does not separately disclose in the same statement or note. [Refer: Profit (loss)] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 7 -IssueDate 2023-01-01 -Paragraph 20 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2023-en-r&anchor=para_20_b&doctype=Standard -URIDate 2023-03-23 + Details
Name: | ifrs-full_OtherAdjustmentsForNoncashItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of material non-cash items other than depreciation and amortisation. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2023-01-01 -Paragraph 28 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2023-en-r&anchor=para_28_e&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2023-01-01 -Paragraph 23 -Subparagraph i -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2023-en-r&anchor=para_23_i&doctype=Standard -URIDate 2023-03-23 + Details
Name: | ifrs-full_OtherMaterialNoncashItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount used (ie incurred and charged against the provision) for other provisions. [Refer: Other provisions] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 37 -IssueDate 2023-01-01 -Paragraph 84 -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=37&code=ifrs-tx-2023-en-r&anchor=para_84_c&doctype=Standard -URIDate 2023-03-23 + Details
Name: | ifrs-full_ProvisionUsedOtherProvisions
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | agi_FairValueAdjustmentAxis=agi_SilverStreamMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | agi_FairValueAdjustmentAxis=agi_MilestonePaymentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfProvisionsAxis=ifrs-full_ProvisionForDecommissioningRestorationAndRehabilitationCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |