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v3.25.1

Operating Context - Additional Information (Details) R$ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2024 BRL (R$) Number | Dec. 31, 2023 BRL (R$) | Dec. 31, 2022 BRL (R$) | Dec. 27, 2024 BRL (R$) | Sep. 27, 2024 BRL (R$)
IfrsStatementLineItems [Line Items] |  |  |  |  |
Negative consolidated working capital | R$ (1,914) | R$ (1,224) |  |  |
Principal amount |  |  |  | R$ 200 | R$ 2,436
Percentage of share | 100.00% |  |  |  |
Repayments of bonds, notes and debentures | R$ 2,975 | R$ 2,679 | R$ 2,613 |  |
Average Debt Maturity | 4 years 9 months 18 days | 2 years 9 months 18 days |  |  |
Number Of Reportable Segments | Number | 6 |  |  |  |
Cemig GT [Member] |  |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |  |
Repayments of bonds, notes and debentures | R$ 3,931 |  |  |  |
Cemig GT [Member] | Alianca Energia SA [Member] |  |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |  |
Percentage of share | 45.00% |  |  |  |
Total Considerations | R$ 2,737 |  |  |  |
Debentures Tenth and Elventh Issue [Member] | Cemig D [Member] |  |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |  |
Principal amount | R$ 4,500 |  |  |  |

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