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30. RELATED PARTY TRANSACTIONS (Details Narrative) - BRL (R$) R$ in Millions |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Dec. 27, 2019 | Nov. 25, 2019 | Jun. 30, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2017
Disclosure of transactions between related parties [line items] |  |  |  |  |  |
Deliver contracted supply amount |  |  |  |  | R$ 40.0 |
Loss on realization of the receivables |  |  | R$ 688.0 |  |  |
In-court reorganization loan amount | R$ 6.5 | R$ 10.0 |  | R$ 20.0 |  |
Description of contract interest rate |  |  |  | The contracts specify interest equal to 100% of the accumulated variation in the DI rate, plus an annual spread, applied pro rata die (on 252-business-days basis), of 1.083% for the DIP contract and 2.5% for the DIP2 contract, up to the date of respective full payment. |  |
Related parties [member] |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |
Aggregate amounts of legal actions |  |  |  | R$ 119.0 | 98.0 |
Related parties [member] | Cemig D [member] |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |
Public lighting contribution amount |  |  |  |  | 190.0 |
Due and unpaid payment of debits relating to supply of power |  |  |  |  |  | R$ 113.0
Loss on realization of the receivables |  |  |  | 210.0 |  |
Related parties [member] | Cemig [member] |  |  |  |  |  |
Disclosure of transactions between related parties [line items] |  |  |  |  |  |
Aggregate amounts of legal actions |  |  |  | R$ 41.0 | R$ 32.0 |

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