XML 140 R104.htm IDEA: XBRL DOCUMENT
v3.22.1

The changes in these concession financial assets are as follows: (Details) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
IfrsStatementLineItems [Line Items] |  |  |
Beginning Balance | R$ 2,550 | R$ 2,468 | R$ 2,409
Monetary updating | 523 | 347 | 318
Amounts received | (281) | (265) | (259)
Ending Balance | 2,792 | 2,550 | 2,468
Cemig geracao tres marias sa [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Beginning Balance | 1,447 | 1,402 | 1,370
Monetary updating | 287 | 188 | 171
Amounts received | (150) | (143) | (139)
Ending Balance | 1,584 | 1,447 | 1,402
Cemig Geracao Salto Grande S A [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Beginning Balance | 454 | 440 | 430
Monetary updating | 90 | 59 | 54
Amounts received | (47) | (45) | (44)
Ending Balance | 497 | 454 | 440
Cemig Geracao Itutinga S A [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Beginning Balance | 171 | 165 | 161
Monetary updating | 37 | 25 | 23
Amounts received | (21) | (19) | (19)
Ending Balance | 187 | 171 | 165
Cemig Geracao Camargos S A [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Beginning Balance | 128 | 124 | 120
Monetary updating | 27 | 18 | 17
Amounts received | (15) | (14) | (13)
Ending Balance | 140 | 128 | 124
Cemig Geracao Sul S A [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Beginning Balance | 167 | 161 | 157
Monetary updating | 38 | 26 | 24
Amounts received | (21) | (20) | (20)
Ending Balance | 184 | 167 | 161
Cemig Geracao Leste S A [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Beginning Balance | 114 | 110 | 107
Monetary updating | 27 | 19 | 18
Amounts received | (16) | (15) | (15)
Ending Balance | 125 | 114 | 110
Cemig Geracao Oeste S A [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Beginning Balance | 69 | 66 | 64
Monetary updating | 17 | 12 | 11
Amounts received | (11) | (9) | (9)
Ending Balance | R$ 75 | R$ 69 | R$ 66

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

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- References No definition available. + Details
Name: | cig_IfrsStatementLineItems
Namespace Prefix: | cig_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Monetary updating. + References No definition available. + Details
Name: | cig_MonetaryUpdating
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of consideration paid or received in respect of both obtaining and losing control of subsidiaries or other businesses. [Refer: Subsidiaries [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 7 -IssueDate 2021-01-01 -Paragraph 40 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2021-en-r&anchor=para_40_a&doctype=Standard -URIDate 2021-03-24 + Details
Name: | ifrs-full_ConsiderationPaidReceived
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Details
Name: | ifrs-full_ServiceConcessionArrangementsAxis=cig_CemigGeracaoTresMariasSAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
Name: | ifrs-full_ServiceConcessionArrangementsAxis=cig_CemigGeracaoSaltoGrandeSAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
Name: | ifrs-full_ServiceConcessionArrangementsAxis=cig_CemigGeracaoItutingaSAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
Name: | ifrs-full_ServiceConcessionArrangementsAxis=cig_CemigGeracaoCamargosSAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
Name: | ifrs-full_ServiceConcessionArrangementsAxis=cig_CemigGeracaoSulSAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
Name: | ifrs-full_ServiceConcessionArrangementsAxis=cig_CemigGeracaoLesteSAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
Name: | ifrs-full_ServiceConcessionArrangementsAxis=cig_CemigGeracaoOesteSAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |