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- References

No definition available.

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- References

No definition available.

Name:	cig_SymbolicPayment
Namespace Prefix:	cig_
Data Type:	xbrli:monetaryItemType
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The amount of compensation from third parties for items of property, plant and equipment that were impaired, lost or given up that is included in profit or loss. [Refer: Profit (loss); Property, plant and equipment]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 16
-IssueDate 2022-03-24
-Paragraph 74A
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=16&code=ifrs-tx-2022-en-r&anchor=para_74A_a&doctype=Standard
-URIDate 2022-03-24

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

The amount of interest recognised as a receivable.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2022-03-24
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2022-03-24

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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 2022-03-24
-Paragraph B64
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2022-en-r&anchor=para_B64_c&doctype=Appendix&subtype=B
-URIDate 2022-03-24

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Data Type:	dtr-types:percentItemType
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The amount of revenue arising from the sale of goods. [Refer: Revenue]

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

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Name:	srt_CounterpartyNameAxis=cig_AtivasDataCenterSAMember
Namespace Prefix:
Data Type:	na
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Name:	srt_CounterpartyNameAxis=cig_SondaMember
Namespace Prefix:
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