XML 99 R73.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Supplemental Cash Flow Information (Other Non-cash Items) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Disclosure of Cash Flow Statement [Abstract] |  |
Unrealized loss on non-hedging derivatives | $ 0.6 | $ 0.4
Payment for reclamation activities | (2.0) | (0.9)
Interest received | 3.4 | 2.8
Credit facility standby fees | (1.8) | (1.8)
Reduction of obligation to renounce flow-through exploration expenditures | (0.6) | (0.6)
Loss on disposal of assets | 0.7 | 6.1
Payment of transaction costs incurred by Richmont Mines (note 5) | (8.0) | 0.0
Other non-cash items | (0.7) | 0.5
Other adjustments for non-cash items | $ (8.4) | $ 6.5

X
- Definition Credit Facility Standby Fees + References No definition available. + Details
Name: | agi_CreditFacilityStandbyFees
Namespace Prefix: | agi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Disclosure of Cash Flow Statement [Abstract] + References No definition available. + Details
Name: | agi_DisclosureofCashFlowStatementAbstract
Namespace Prefix: | agi_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Noncash Net Realizable Value Adjustments + References No definition available. + Details
Name: | agi_NoncashNetRealizableValueAdjustments
Namespace Prefix: | agi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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 gains (losses) on changes in the fair value of derivatives to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: At fair value [member]; Derivatives [member]; Profit (loss)] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 7 -IssueDate 2019-01-01 -Paragraph 20 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_20&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_AdjustmentsForGainsLossesOnChangeInFairValueOfDerivatives
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cash inflow from interest received, classified as investing activities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 7 -IssueDate 2019-01-01 -Paragraph 31 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_31&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_InterestReceivedClassifiedAsInvestingActivities
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 2019-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard -URIDate 2019-03-27 + 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 2019-01-01 -Paragraph 20 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_20_b&doctype=Standard -URIDate 2019-03-27 + 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 2019-01-01 -Paragraph 23 -Subparagraph i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2019-en-r&anchor=para_23_i&doctype=Standard -URIDate 2019-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2019-01-01 -Paragraph 28 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2019-en-r&anchor=para_28_e&doctype=Standard -URIDate 2019-03-27 + Details
Name: | ifrs-full_OtherMaterialNoncashItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration