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28. OPERATING COSTS AND EXPENSES (Details Narrative) R$ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 BRL (R$) N | Dec. 31, 2020 BRL (R$) N | Dec. 31, 2019 BRL (R$)
Disclosure Of Operating Costs And Expenses [line items] |  |  |
Period of eligibility for the severance program |  | 25 years |
Penalty in percentage |  | 20.00% |
Legal payments for severance percentage |  | 50.00% |
Programmed voluntary retirement plan expense | R$ 21 |  |
Number of employees completing severance | N | 155 |  |
Right of use |  | R$ (9) | R$ 32
Action provisioned at the cost |  | 119 | 98
Impairment of intangible assets |  | 22 |
Cemig [member] |  |  |
Disclosure Of Operating Costs And Expenses [line items] |  |  |
Right of use |  | 41 | R$ 32
PDVP 2020 [member] |  |  |
Disclosure Of Operating Costs And Expenses [line items] |  |  |
Programmed voluntary retirement plan expense |  | R$ 59 |
Number of employees completing severance | N |  | 396 |

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