XML 98 R64.htm IDEA: XBRL DOCUMENT
v3.22.1

Share Capital (Stock Options) (Details) | 12 Months Ended
--- | ---
Dec. 31, 2021 shares $ / shares | Dec. 31, 2020 shares $ / shares
Disclosure of share capital, reserves and other equity interest [Abstract] |  |
Number of options outstanding | shares | 3,476,579 | 4,465,262
Granted | shares | 1,165,147 | 876,425
Exercised | shares | (40,000) | (1,653,361)
Expired | shares |  | (211,747)
Number of options outstanding | shares | 4,601,726 | 3,476,579
Weighted average exercise price of share options outstanding (CAD$) | $ 6.80 | $ 6.59
Weighted average exercise price of share options granted (CAD$) | 9.38 | 7.66
Weighted average exercise price of share options exercised (CAD$) | 5.16 | 6.15
Weighted average exercise price of share options expired (CAD$) |  | 11.02
Weighted average exercise price of share options outstanding (CAD$) | 7.47 | 6.80
Weighted average share price for share options in share-based payment arrangement exercised during period at date of exercise | $ 10.94 | $ 10.90

X
- Definition Disclosure of share capital, reserves and other equity interest [Abstract] + References No definition available. + Details
Name: | agi_DisclosureofsharecapitalreservesandotherequityinterestAbstract
Namespace Prefix: | agi_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of share options outstanding in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2021-01-01 -Paragraph 45 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_d&doctype=Standard -URIDate 2021-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2021-01-01 -Paragraph 45 -Subparagraph b -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_i&doctype=Standard -URIDate 2021-03-24 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2021-01-01 -Paragraph 45 -Subparagraph b -Clause vi -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_vi&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_NumberOfOutstandingShareOptions
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of share options exercised in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2021-01-01 -Paragraph 45 -Subparagraph b -Clause iv -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_iv&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_NumberOfShareOptionsExercisedInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of share options expired in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2021-01-01 -Paragraph 45 -Subparagraph b -Clause v -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_v&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_NumberOfShareOptionsExpiredInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of share options granted in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2021-01-01 -Paragraph 45 -Subparagraph b -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_ii&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_NumberOfShareOptionsGrantedInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average exercise price of share options exercised in a share-based payment arrangement. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2021-01-01 -Paragraph 45 -Subparagraph b -Clause iv -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_iv&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_WeightedAverageExercisePriceOfShareOptionsExercisedInSharebasedPaymentArrangement2019
Namespace Prefix: | ifrs-full_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average exercise price of share options expired in a share-based payment arrangement. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2021-01-01 -Paragraph 45 -Subparagraph b -Clause v -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_v&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_WeightedAverageExercisePriceOfShareOptionsExpiredInSharebasedPaymentArrangement2019
Namespace Prefix: | ifrs-full_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average exercise price of share options granted in a share-based payment arrangement. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2021-01-01 -Paragraph 45 -Subparagraph b -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_ii&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_WeightedAverageExercisePriceOfShareOptionsGrantedInSharebasedPaymentArrangement2019
Namespace Prefix: | ifrs-full_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average share price at the date of exercise for share options that are exercised in a share-based payment arrangement. [Refer: Share-based payment arrangements [member]; Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2021-01-01 -Paragraph 45 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_c&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_WeightedAverageExercisePriceOfShareOptionsInSharebasedPaymentArrangementExercisedDuringPeriodAtDateOfExercise2019
Namespace Prefix: | ifrs-full_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average exercise price of share options outstanding in a share-based payment arrangement. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2021-01-01 -Paragraph 45 -Subparagraph b -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_i&doctype=Standard -URIDate 2021-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2021-01-01 -Paragraph 45 -Subparagraph b -Clause vi -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_vi&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_WeightedAverageExercisePriceOfShareOptionsOutstandingInSharebasedPaymentArrangement2019
Namespace Prefix: | ifrs-full_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant