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22. LOANS, FINANCING AND DEBENTURES (Detaills Narrative) - BRL (R$) R$ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 26, 2020 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of detailed information about borrowings [line items] |  |  |  |
Average rate of capitalization rate |  | 5.39% |  |
Promissory Notes First Issue Single Series [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Aggregate amount | R$ 850 |  |  |
Maturity term | 11 years |  |  |
Interest rate | 5.27% |  |  |
Cemig GT [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Aggregate amount |  | R$ 50 |  |
Restated [member] |  |  |  |
Disclosure of detailed information about borrowings [line items] |  |  |  |
Average rate of capitalization rate |  |  | 6.79% | 9.64%

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