XML 165 R150.htm IDEA: XBRL DOCUMENT
v3.23.1

POST-EMPLOYMENT OBLIGATIONS (Details 1) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
IfrsStatementLineItems [Line Items] |  |  |  |  |
Defined-benefit obligation on December 31, 2021 |  | R$ 14,778 | R$ 15,561 | R$ 17,242 | R$ 17,022
Cost of current service |  | 14 | 18 | 27 | 26
Interest on actuarial obligation |  | 1,662 |  | 1,159 | 1,147
Actuarial losses (gains): |  |  |  |  |
Due to changes in demographic assumptions |  |  | (8) | 486 | 534
Due to changes in financial assumptions |  |  | (1,168) | (2,777) | (565)
Due to adjustments based on experience |  |  | 83 | 1,005 | 148
Due to changes and adjustments |  |  | (1,093) | (1,286) | 117
Benefits paid |  |  | (1,296) | (1,166) | (1,070)
Past service cost | [1] |  | (4) | (415) |
Actuarial losses (gains): |  |  | 1,592 |  |
Defined-benefit obligation on December 31, 2022 |  |  | 14,778 | 15,561 | 17,242
Pension plans and retirement supplement plans [member] |  |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |  |
Defined-benefit obligation on December 31, 2021 |  | 11,404 | 12,026 | 13,308 | 13,285
Cost of current service |  |  | 2 | 2 | 1
Interest on actuarial obligation |  | 1,276 |  | 883 | 887
Actuarial losses (gains): |  |  |  |  |
Due to changes in demographic assumptions |  |  | (7) | 378 | 135
Due to changes in financial assumptions |  |  | (857) | (2,393) | (375)
Due to adjustments based on experience |  |  | 106 | 828 | 289
Due to changes and adjustments |  |  | (758) | (1,187) | 49
Benefits paid |  |  | (1,086) | (980) | (914)
Past service cost | [1] |  | (4) |  |
Actuarial losses (gains): |  |  | 1,224 |  |
Defined-benefit obligation on December 31, 2022 |  |  | 11,404 | 12,026 | 13,308
Health plan [member] |  |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |  |
Defined-benefit obligation on December 31, 2021 |  | 3,314 | 3,469 | 3,319 | 3,102
Cost of current service |  | 14 | 16 | 21 | 21
Interest on actuarial obligation |  | 379 |  | 232 | 215
Actuarial losses (gains): |  |  |  |  |
Due to changes in demographic assumptions |  |  | (1) | 122 | 395
Due to changes in financial assumptions |  |  | (305) | (252) | (152)
Due to adjustments based on experience |  |  | (20) | 200 | (119)
Due to changes and adjustments |  |  | (326) | 70 | 124
Benefits paid |  |  | (206) | (173) | (143)
Past service cost | [1] |  |  |  |
Actuarial losses (gains): |  |  | 361 |  |
Defined-benefit obligation on December 31, 2022 |  |  | 3,314 | 3,469 | 3,319
Dental plan [member] |  |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |  |
Defined-benefit obligation on December 31, 2021 |  | 60 | 66 | 64 | 61
Cost of current service |  |  |  | 1 | 1
Interest on actuarial obligation |  | 7 |  | 5 | 4
Actuarial losses (gains): |  |  |  |  |
Due to changes in demographic assumptions |  |  |  | 1 | 4
Due to changes in financial assumptions |  |  | (6) | (5) | (4)
Due to adjustments based on experience |  |  | (3) | 3 | 1
Due to changes and adjustments |  |  | (9) | (1) | 1
Benefits paid |  |  | (4) | (3) | (3)
Past service cost | [1] |  |  |  |
Actuarial losses (gains): |  |  | 7 |  |
Defined-benefit obligation on December 31, 2022 |  |  | 60 | 66 | 64
Life Insurance Plan [Member] |  |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |  |
Defined-benefit obligation on December 31, 2021 |  |  |  | 551 | 574
Cost of current service |  |  |  | 3 | 3
Interest on actuarial obligation |  |  |  | 39 | 41
Actuarial losses (gains): |  |  |  |  |
Due to changes in demographic assumptions |  |  |  | (15) |
Due to changes in financial assumptions |  |  |  | (127) | (34)
Due to adjustments based on experience |  |  |  | (26) | (23)
Due to changes and adjustments |  |  |  | (168) | (57)
Benefits paid |  |  |  | (10) | (10)
Past service cost | [1] |  |  | (415) |
Actuarial losses (gains): |  |  |  |  |
Defined-benefit obligation on December 31, 2022 |  |  |  |  | R$ 551
[1] | Due to the alterations made in the Collective Work Agreement for 2021-23, for offer and payment of life insurance for the employees and former employees, the Company understood that the post-retirement benefit in question had been entirely canceled, and as a result wrote down the balance of the obligation, remeasured using the revised actuarial assumptions.

X
- Definition Actuarial gains (losses) arising from adjustments based on experience net defined benefit liability (asset). + References No definition available. + Details
Name: | cig_ActuarialGainsLossesArisingFromAdjustmentsBasedOnExperienceNetDefinedBenefitLiabilityAsset
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of due to change in financial assumptions. + References No definition available. + Details
Name: | cig_DueToChangesInFinancialAssumptions
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_PastServiceCost1
Namespace Prefix: | cig_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in demographic assumptions that result in remeasurements of the net defined benefit liability (asset). Demographic assumptions deal with matters such as: (a) mortality; (b) rates of employee turnover, disability and early retirement; (c) the proportion of plan members with dependants who will be eligible for benefits; (d) the proportion of plan members who will select each form of payment option available under the plan terms; and (e) claim rates under medical plans. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2022-03-24 -Paragraph 141 -Subparagraph c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_141_c_ii&doctype=Standard -URIDate 2022-03-24 + Details
Name: | ifrs-full_ActuarialGainsLossesArisingFromChangesInDemographicAssumptionsNetDefinedBenefitLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2022-03-24 -Paragraph 141 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_141_a&doctype=Standard -URIDate 2022-03-24 + Details
Name: | ifrs-full_CurrentServiceCostNetDefinedBenefitLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from the remeasurement of that net defined benefit liability (asset). [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2022-03-24 -Paragraph 141 -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_141_c&doctype=Standard -URIDate 2022-03-24 + Details
Name: | ifrs-full_GainLossOnRemeasurementOfNetDefinedBenefitLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

X
- Definition The increase (decrease) in the net defined benefit liability (asset). [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2022-03-24 -Paragraph 141 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_141&doctype=Standard -URIDate 2022-03-24 + Details
Name: | ifrs-full_IncreaseDecreaseInNetDefinedBenefitLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from the passage of time. [Refer: Interest expense; Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2022-03-24 -Paragraph 141 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_141_b&doctype=Standard -URIDate 2022-03-24 + Details
Name: | ifrs-full_InterestExpenseIncomeNetDefinedBenefitLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2022-03-24 -Paragraph 140 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_140_a&doctype=Standard -URIDate 2022-03-24 + Details
Name: | ifrs-full_LiabilityAssetOfDefinedBenefitPlans
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2022-03-24 -Paragraph 141 -Subparagraph g -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_141_g&doctype=Standard -URIDate 2022-03-24 + Details
Name: | ifrs-full_PaymentsFromPlanNetDefinedBenefitLiabilityAsset
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | ifrs-full_DefinedBenefitPlansAxis=cig_PensionPlansAndRetirementSupplementPlansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_DefinedBenefitPlansAxis=cig_HealthPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_DefinedBenefitPlansAxis=cig_DentalPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_DefinedBenefitPlansAxis=cig_LifeInsurancePlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |