XML 196 R181.htm IDEA: XBRL DOCUMENT
v3.23.1

OPERATING COSTS AND EXPENSES (Details) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | R$ 14,614 | R$ 16,101 | R$ 12,111
Basic network usage charges | 2,671 | 3,337 | 1,748
Gas purchased for resale | 2,735 | 2,011 | 1,083
Total costs of energy and gas | 20,020 | 21,449 | 14,942
Supply from itaipu binacional [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 1,644 | 1,946 | 1,990
Physical guarantee quota contracts [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 925 | 832 | 780
Quotas for Angra I and II nuclear plants [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 357 | 244 | 303
Spot market [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 530 | 1,224 | 1,497
Proinfa program [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 598 | 401 | 318
Bilateral contracts [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 493 | 418 | 333
Energy acquired in regulated market auctions [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 3,334 | 6,242 | 3,334
Energy acquired in the free market [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 6,003 | 4,976 | 3,977
Distributed generation ('geracao distribuida') [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | 1,977 | 1,268 | 678
PIS/pasep and cofins credits [member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Energy purchased for resale | (1,247) | (1,450) | (1,099)
Basic network usage charges | (304) | (367) | (202)
Transmission Charges Basic Grid [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Basic network usage charges | 2,925 | 3,663 | 1,910
Distribution Charges [Member] |  |  |
IfrsStatementLineItems [Line Items] |  |  |
Basic network usage charges | R$ 50 | R$ 41 | R$ 40

X
- References No definition available. + Details
Name: | cig_BasicNetworkUsageCharges
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Energy purchased for resale. + References No definition available. + Details
Name: | cig_EnergyPurchasedForResale
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | cig_GasPurchasedForResale
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

X
- References No definition available. + Details
Name: | cig_TotalCostsOfEnergyAndGas
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=cig_SupplyFromItaipuBinacionalMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=cig_PhysicalGuaranteeQuotaContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=cig_QuotasForAngraIAndIINuclearPlantsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=cig_SpotMarketMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=cig_ProinfaProgramMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=cig_BilateralContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=cig_EnergyAcquiredInRegulatedMarketAuctionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=cig_EnergyAcquiredInTheFreeMarketMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=cig_DistributedGenerationGeracaoDistribuidaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=cig_PISPasepAndCofinsCreditsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=cig_TransmissionChargesBasicGridMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ProductsAndServicesAxis=cig_DistributionChargesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |