XML 127 R106.htm IDEA: XBRL DOCUMENT v3.25.1

Concession Financial and Sector Assets and Liabilities - Schedule of Changes in Concession Financial Assets Related to Concession Grant Fee (Details) - BRL (R$) R$ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
IfrsStatementLineItems [Line Items]
Beginning Balance	R$ 3,031	R$ 2,950	R$ 2,792
Monetary updating	447	412	467
Amounts received	(343)	(331)	(309)
Classification as held for sale	(36)
Ending Balance	3,099	3,031	2,950
Cemig Geracao Tres Marias S A [Member]
IfrsStatementLineItems [Line Items]
Beginning Balance	1,716	1,672	1,584
Monetary updating	242	222	254
Amounts received	(184)	(178)	(166)
Classification as held for sale
Ending Balance	1,774	1,716	1,672
Cemig geracao salto grande sa [member]
IfrsStatementLineItems [Line Items]
Beginning Balance	539	525	497
Monetary updating	76	70	80
Amounts received	(58)	(56)	(52)
Classification as held for sale
Ending Balance	557	539	525
Cemig Geracao Itutinga S A [Member]
IfrsStatementLineItems [Line Items]
Beginning Balance	204	198	187
Monetary updating	32	30	33
Amounts received	(25)	(24)	(22)
Classification as held for sale
Ending Balance	211	204	198
Cemig Geracao Camargos S A [Member]
IfrsStatementLineItems [Line Items]
Beginning Balance	152	148	140
Monetary updating	24	22	25
Amounts received	(18)	(18)	(17)
Classification as held for sale
Ending Balance	158	152	148
Cemig Geracao Sul S A [Member]
IfrsStatementLineItems [Line Items]
Beginning Balance	201	195	184
Monetary updating	33	31	34
Amounts received	(26)	(25)	(23)
Classification as held for sale	(22)
Ending Balance	186	201	195
Cemig Geracao Leste S A [Member]
IfrsStatementLineItems [Line Items]
Beginning Balance	137	133	125
Monetary updating	25	23	26
Amounts received	(20)	(19)	(18)
Classification as held for sale
Ending Balance	142	137	133
Cemig Geracao Oeste S A [Member]
IfrsStatementLineItems [Line Items]
Beginning Balance	82	79	75
Monetary updating	15	14	15
Amounts received	(12)	(11)	(11)
Classification as held for sale	(14)
Ending Balance	R$ 71	R$ 82	R$ 79

X

- Definition

Auction concession.

+ References

No definition available.

+ Details

Name:	cig_AuctionConcession
Namespace Prefix:	cig_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The amount of financial assets reclassified as held for sale.

+ References

No definition available.

+ Details

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

X

- Definition

Ifrs Statement Line Items

+ References

No definition available.

+ Details

Name:	cig_IfrsStatementLineItems
Namespace Prefix:	cig_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Revenue from concession grant fee.

+ References

No definition available.

+ Details

Name:	cig_RevenueFromConcessionGrantFee
Namespace Prefix:	cig_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

The amount of consideration paid or received in respect of both obtaining and losing control of subsidiaries or other businesses. [Refer: Total for all subsidiaries [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2024-01-01
-Paragraph 40
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2024-en-r&anchor=para_40_a&doctype=Standard
-URIDate 2024-03-27

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

X

- Details

Name:	ifrs-full_ServiceConcessionArrangementsAxis=cig_CemigGeracaoTresMariasSAMember
Namespace Prefix:
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Balance Type:
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X

- Details

Name:	ifrs-full_ServiceConcessionArrangementsAxis=cig_CemigGeracaoSaltoGrandeSAMember
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Balance Type:
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X

- Details

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X

- Details

Name:	ifrs-full_ServiceConcessionArrangementsAxis=cig_CemigGeracaoCamargosSAMember
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- Details

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- Details

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- Details

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