XML 99 R68.htm IDEA: XBRL DOCUMENT v3.19.1

Share Capital (Dividends) (Details) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
	Apr. 28, 2017	Dec. 31, 2018
Disclosure of share capital, reserves and other equity interest [Abstract]
Dividends paid, ordinary shares	$ 3.9	$ 7.8
Dividends paid, ordinary shares per share		$ 0.01

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 amount of dividends paid by the entity on ordinary shares. [Refer: Ordinary shares [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 34
-IssueDate 2018-01-01
-Paragraph 16A
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=34&date=2018-03-01&anchor=para_16A_f&doctype=Standard
-URIDate 2018-03-16

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

The amount of dividends paid per ordinary share.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 34
-IssueDate 2018-01-01
-Paragraph 16A
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=34&date=2018-03-01&anchor=para_16A_f&doctype=Standard
-URIDate 2018-03-16

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Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration