XML 102 R68.htm IDEA: XBRL DOCUMENT
v3.22.1

Share Capital (Earnings (loss) per share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Disclosure of share capital, reserves and other equity interest [Abstract] |  |
Net (loss) earnings | $ (66.7) | $ 144.2
Weighted average number of common shares outstanding (in shares) | 392,649 | 391,675
Basic loss per share (usd per share) | $ (0.17) | $ 0.37
Dilutive effect of potential common share equivalents (in shares) | 0 | 3,187
Diluted weighted average number of common shares outstanding (in shares) | 392,649 | 394,862
Diluted loss per share (usd per share) | $ (0.17) | $ 0.37

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 weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2021-01-01 -Paragraph 70 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2021-en-r&anchor=para_70_b&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_AdjustedWeightedAverageShares
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator) divided by the weighted average number of ordinary shares outstanding during the period (the denominator). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2021-01-01 -Paragraph 66 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2021-en-r&anchor=para_66&doctype=Standard -URIDate 2021-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2021-01-01 -Paragraph 67 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2021-en-r&anchor=para_67&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_BasicEarningsLossPerShare
Namespace Prefix: | ifrs-full_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator), divided by the weighted average number of ordinary shares outstanding during the period (the denominator), both adjusted for the effects of all dilutive potential ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2021-01-01 -Paragraph 66 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2021-en-r&anchor=para_66&doctype=Standard -URIDate 2021-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2021-01-01 -Paragraph 67 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2021-en-r&anchor=para_67&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_DilutedEarningsLossPerShare
Namespace Prefix: | ifrs-full_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of dilutive potential ordinary shares that relate to the assumed exercise of the entity's share options. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 33 -IssueDate 2021-01-01 -Paragraph 70 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2021-en-r&anchor=para_70_b&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_DilutiveEffectOfShareOptionsOnNumberOfOrdinaryShares
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The total of income less expenses from continuing and discontinued operations, excluding the components of other comprehensive income. [Refer: Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 7 -IssueDate 2021-01-01 -Paragraph 18 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2021-en-r&anchor=para_18_b&doctype=Standard -URIDate 2021-03-24 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 1 -IssueDate 2021-01-01 -Paragraph 24 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=1&code=ifrs-tx-2021-en-r&anchor=para_24_b&doctype=Standard -URIDate 2021-03-24 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 1 -IssueDate 2021-01-01 -Paragraph 32 -Subparagraph a -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=1&code=ifrs-tx-2021-en-r&anchor=para_32_a_ii&doctype=Standard -URIDate 2021-03-24 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2021-01-01 -Paragraph 28 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_28_b&doctype=Standard -URIDate 2021-03-24 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Note Effective on first application of IFRS 9 -Name IFRS -Number 4 -IssueDate 2021-01-01 -Paragraph 39L -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=4&code=ifrs-tx-2021-en-b&anchor=para_39L_e&doctype=Standard -URIDate 2021-03-24 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2021-01-01 -Paragraph 23 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2021-en-r&anchor=para_23&doctype=Standard -URIDate 2021-03-24 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Note Effective 2023-01-01 -Name IFRS -Number 17 -IssueDate 2021-01-01 -Paragraph 113 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=17&code=ifrs-tx-2021-en-r&anchor=para_113_b&doctype=Standard -URIDate 2021-03-24 Reference 8: http://www.xbrl.org/2003/role/exampleRef -Name IFRS -Number 12 -IssueDate 2021-01-01 -Paragraph B10 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2021-en-r&anchor=para_B10_b&doctype=Appendix&subtype=B -URIDate 2021-03-24 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 106 -Subparagraph d -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_106_d_i&doctype=Standard -URIDate 2021-03-24 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2021-01-01 -Paragraph 81A -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_81A_a&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_ProfitLoss
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The number of ordinary shares outstanding at the beginning of the period, adjusted by the number of ordinary shares bought back or issued during the period multiplied by a time-weighting factor. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2021-01-01 -Paragraph 70 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2021-en-r&anchor=para_70_b&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_WeightedAverageShares
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration