The increase in associates and joint ventures.

No definition available.

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Namespace Prefix:	ach_
Data Type:	xbrli:monetaryItemType
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- Definition

The increase in associates and joint ventures resulting from capital injections.

+ References

No definition available.

+ Details

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

- Definition

The decrease in associates and joint ventures resulting from disposals.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The increase (decrease) in associates and joint ventures resulting from changes that the entity does not separately disclose in the same statement or note.

+ References

No definition available.

+ Details

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- Definition

Investments in joint ventures accounted for using equity method, registered and paid-in capital

+ References

No definition available.

+ Details

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

- Definition

This concept does not have any references.

+ References

No definition available.

+ Details

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- Definition

The proportion of profit sharing percentage in a associate attributable to the entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	ach_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of interest transferred from subsidiary to associate due to transmission.

+ References

No definition available.

+ Details

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Namespace Prefix:	ach_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of dividends that the company has declared but not yet paid.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2020-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_55&doctype=Standard
-URIDate 2020-01-01

+ Details

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Balance Type:	credit
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- Definition

The amount of investments in associates accounted for using the equity method. [Refer: Associates [member]; Investments accounted for using equity method]

+ References

+ Details

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

- Definition

The proportion of ownership interest in an associate attributable to the entity. [Refer: Associates [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2020-01-01
-Paragraph 17
-Subparagraph b
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2020-en-r&anchor=para_17_b_iii&doctype=Standard
-URIDate 2020-01-01

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2020-01-01
-Paragraph 16
-Subparagraph b
-Clause iii
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
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-Subparagraph a
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-URIDate 2020-01-01

+ Details

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- Definition

The proportion of the voting rights in an associate held by the entity. [Refer: Associates [member]]

+ References

+ Details

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

- Definition

The cash outflow for the purchase of interests in associates. [Refer: Associates [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 7
-IssueDate 2020-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2020-en-r&anchor=para_16&doctype=Standard
-URIDate 2020-01-01

+ Details

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Balance Type:	credit
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- Definition

The entity's share of the profit (loss) of associates accounted for using the equity method. [Refer: Associates [member]; Investments accounted for using equity method; Profit (loss)]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Number 1
-IssueDate 2020-01-01
-Paragraph 85
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+ Details

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- Details

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- Details

Name:	ifrs-full_SignificantInvestmentsInAssociatesAxis=ach_HeqingYixinAluminumIndustryCoLtdMember
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- Details

Name:	ifrs-full_JointVenturesAxis=ach_GuangxiHuayinAluminumCo.LtdMember
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INVESTMENTS IN JOINT VENTURES AND ASSOCIATES - Associates (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2020 CNY (¥)	Dec. 31, 2019 CNY (¥)	Dec. 31, 2018 CNY (¥)
Movements in investments in associates
As at January 1		¥ 9,512,401	¥ 6,363,462
Subsidiaries changed into an associate		7,473	16,283
Capital reduction		(14,850)	(20,250)
Share of the joint ventures associates profits and losses for the year	$ 22,335	145,737	48,767	¥ 39,335
Cash dividends declared		(480,397)	(50,314)
Share of changes in reserves		3,046	(7,811)
As at December 31	1,405,887	9,173,410	9,512,401	6,363,462
Total subscription amount	$ 1,145	7,473	2,653,244	¥ 266,300
Associates Other than Yunnan Aluminum and Yixin Aluminum
Movements in investments in associates
Capital injections			729,368
Yunnan Aluminium
Movements in investments in associates
Investment made in associates			1,491,736
Registered and paid-in capital		¥ 3,128,207
Ownership interest in associate (in percent)	10.04%	10.04%
Voting power in associate (as a percent)	10.04%	10.04%
Profit sharing in associate (as a percent)	10.04%	10.04%
Investment to Heqing Yixin Aluminum Industry Co., Ltd.
Movements in investments in associates
Investment made in associates			¥ 941,160
Guangxi Huayin Aluminum Co., Ltd.
Movements in investments in associates
Registered and paid-in capital		¥ 2,441,987