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The amount recognised as of the acquisition date for income tax payable assumed in a business combination.

No definition available.

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The amount recognised as of the acquisition date for other current assets acquired in a business combination.

No definition available.

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Namespace Prefix:	ach_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The amount recognised as of the acquisition date for other payables and accrued expenses assumed in a business combination.

No definition available.

Name:	ach_OtherPayablesAndAccruedExpensesRecognisedAsOfAcquisitionDate
Namespace Prefix:	ach_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The amount recognised as of the acquisition date for trade and note payables assumed in a business combination.

No definition available.

Name:	ach_TradeAndNotePayablesRecognisedAsOfAcquisitionDate
Namespace Prefix:	ach_
Data Type:	xbrli:monetaryItemType
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The fair value, at acquisition date, of the consideration transferred in a business combination. [Refer: Business combinations [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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-IssueDate 2020-01-01
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

Name:	ifrs-full_AssetsAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The amount recognised as of the acquisition date for cash and cash equivalents acquired in a business combination. [Refer: Cash and cash equivalents; Business combinations [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The amount of an entity’s obligation to transfer goods or services to a customer for which the entity has received consideration (or the amount is due) from the customer.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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Name:	ifrs-full_ContractLiabilities
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

No definition available.

Name:	ifrs-full_DisclosureOfBusinessCombinationsLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The fair value of receivables acquired in a business combination. [Refer: Business combinations [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URIDate 2020-01-01

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amount recognised as of the business combination's acquisition date for goodwill. [Refer: Goodwill; Business combinations [member]]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IFRS
-Number 3
-IssueDate 2020-01-01
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-URIDate 2020-01-01

Name:	ifrs-full_GoodwillRecognisedAsOfAcquisitionDate
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amount recognised as of the acquisition date for net identifiable assets acquired or liabilities assumed in a business combination. [Refer: Business combinations [member]]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IFRS
-Number 3
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-Name IFRS
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-URIDate 2020-01-01

Name:	ifrs-full_IdentifiableAssetsAcquiredLiabilitiesAssumed
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amount recognised as of the acquisition date for inventory acquired in a business combination. [Refer: Inventories; Business combinations [member]]

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

- References

No definition available.

Name:	ifrs-full_LiabilitiesAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The amount of non-controlling interest in the acquiree recognised at the acquisition date for business combinations in which the acquirer holds less than 100 per cent of the equity interests in the acquiree at the acquisition date. [Refer: Business combinations [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URIDate 2020-01-01

Name:	ifrs-full_NoncontrollingInterestInAcquireeRecognisedAtAcquisitionDate
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The percentage of voting equity interests acquired in a business combination. [Refer: Business combinations [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2020-01-01
-Paragraph B64
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-URIDate 2020-01-01

Name:	ifrs-full_PercentageOfVotingEquityInterestsAcquired
Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The amount recognised as of the acquisition date for plant, property and equipment acquired in a business combination. [Refer: Property, plant and equipment; Business combinations [member]]