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16. CONCESSION FINANCIAL AND SECTOR ASSETS AND LIABILITIES (Details 3) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | R$ 2,468 | R$ 2,337 | R$ 2,254
Monetary updating | 317 | 322 | 317
Amounts received | (250) | (250) | (234)
Ending Balance | 2,468 | 2,468 | 2,337
Cemig Geracao Tres Marias Sa [Member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 1,370 | 1,330 | 1,283
Monetary updating | 171 | 174 | 172
Amounts received | (139) | (134) | (125)
Ending Balance | 1,402 | 1,370 | 1,330
Cemig Geracao Salto Grande Sa [Member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 430 | 417 | 417
Monetary updating | 54 | 55 | 54
Amounts received | (44) | (42) | (40)
Ending Balance | 440 | 430 | 417
Cemig Geracao Itutinga Sa [Member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 161 | 156 | 150
Monetary updating | 23 | 23 | 23
Amounts received | (19) | (18) | (17)
Ending Balance | 165 | 161 | 156
Cemig Geracao Camargos S.A. [Member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 120 | 116 | 112
Monetary updating | 17 | 17 | 17
Amounts received | (13) | (13) | (13)
Ending Balance | 124 | 120 | 116
Cemig Geracao Sul S.A. [Member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 157 | 152 | 147
Monetary updating | 24 | 24 | 23
Amounts received | (20) | (19) | (18)
Ending Balance | 161 | 157 | 152
Cemig Geracao Leste S.A. [Member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 107 | 103 | 99
Monetary updating | 18 | 18 | 17
Amounts received | (15) | (14) | (13)
Ending Balance | 110 | 107 | 103
Cemig Geracao Oeste S.A. [Member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 64 | 63 | 60
Monetary updating | 11 | 11 | 11
Amounts received | (9) | (10) | (8)
Ending Balance | R$ 66 | R$ 64 | R$ 63

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