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16. CONCESSION FINANCIAL AND SECTOR ASSETS AND LIABILITIES (Details 2) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 BRL (R$) MW | Dec. 31, 2018 BRL (R$) | Dec. 31, 2017 BRL (R$)
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Installed capacity (MW) | MW |  | 3,601.70 |  |
Net balance of assets based on historical cost |  | R$ 204 |  |
Net balance of assets based on fair value (replacement cost) |  | 816 | R$ 816 |
Amounts received |  | R$ (250) | R$ (250) | R$ (234)
Cemig PCH Marmelos [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 4.00 |  |
Net balance of assets based on historical cost |  | R$ 1 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 4 |  |
Cemig PCH Paciencia [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 4.08 |  |
Net balance of assets based on historical cost |  | R$ 1 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 4 |  |
Cemig PCH Cajuru [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 7.20 |  |
Net balance of assets based on historical cost |  | R$ 4 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 4 |  |
Cemig PCH Martins [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 7.70 |  |
Net balance of assets based on historical cost |  | R$ 2 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 4 |  |
Cemig PCH Joasal [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 8.40 |  |
Net balance of assets based on historical cost |  | R$ 1 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 8 |  |
Cemig PCH Tronqueiras [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 8.50 |  |
Net balance of assets based on historical cost |  | R$ 2 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 12 |  |
Cemig PCH Dona Rita [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2013-09 |  |
Installed capacity (MW) | MW |  | 2.41 |  |
Net balance of assets based on historical cost |  | R$ 1 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 1 |  |
Cemig PCH Peti [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 9.40 |  |
Net balance of assets based on historical cost |  | R$ 1 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 8 |  |
Cemig PCH Gafanhoto [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 14.00 |  |
Net balance of assets based on historical cost |  | R$ 1 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 10 |  |
Cemig PCH Piau [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 18.01 |  |
Net balance of assets based on historical cost |  | R$ 2 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 9 |  |
Usina Hidreletrica Sao Simao [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date | [1] | 2015-01 |  |
Installed capacity (MW) | MW | [1] | 1.710 |  |
Net balance of assets based on historical cost | [1] | R$ 2 |  |
Net balance of assets based on fair value (replacement cost) | [1] | R$ 3 |  |
Usina Hidreletrica Jaguara [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date | [1] | 2013-08 |  |
Installed capacity (MW) | MW | [1] | 424.00 |  |
Net balance of assets based on historical cost | [1] | R$ 40 |  |
Net balance of assets based on fair value (replacement cost) | [1] | R$ 174 |  |
Usina Hidreletrica Miranda [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date | [1] | 2016-12 |  |
Installed capacity (MW) | MW | [1] | 408.00 |  |
Net balance of assets based on historical cost | [1] | R$ 27 |  |
Net balance of assets based on fair value (replacement cost) | [1] | R$ 23 |  |
Usina Hidreletrica Volta Grande [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2017-02 |  |
Installed capacity (MW) | MW |  | 380.00 |  |
Net balance of assets based on historical cost |  | R$ 26 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 70 |  |
Usina Hidreletrica Camargos [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 46.00 |  |
Net balance of assets based on historical cost |  | R$ 8 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 23 |  |
Usina Hidreletrica Itutinga [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 52.00 |  |
Net balance of assets based on historical cost |  | R$ 3 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 7 |  |
Usina Hidreletrica Salto Grande [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 102.00 |  |
Net balance of assets based on historical cost |  | R$ 11 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 39 |  |
Usina Hidreletrica Tres Marias [Member] |  |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |  |
Concession expiration date |  | 2015-07 |  |
Installed capacity (MW) | MW |  | 396.00 |  |
Net balance of assets based on historical cost |  | R$ 71 |  |
Net balance of assets based on fair value (replacement cost) |  | R$ 413 |  |
[1] | Investments made after the Jaguara, Sao Simao and Miranda plants came into operation, in the amounts of R$174, R$3 and R$23, respectively, are recorded as concession financial assets, and the determination of the final amounts to be paid to the Company is in a process of discussion with Aneel (the regulator). Company does not expect losses in realization of these amounts.

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