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14. CONCESSION FINANCIAL AND SECTOR ASSETS AND LIABILITIES (Details 3) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | R$ 2,468 | R$ 2,409 | R$ 2,337
Monetary updating | 347 | 317 | 322
Amounts received | (265) | (250) | (250)
Ending Balance | 2,550 | 2,468 | 2,409
Cemig geracao tres marias s.a. [member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 1,402 | 1,370 |
Monetary updating | 188 | 171 | 174
Amounts received | (143) | (139) | (134)
Ending Balance | 1,447 | 1,402 | 1,370
Cemig geracao salto grande sa [member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 440 | 430 |
Monetary updating | 59 | 54 | 55
Amounts received | (45) | (44) | (42)
Ending Balance | 454 | 440 | 430
Cemig geracao itutinga s.a. [member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 165 | 161 |
Monetary updating | 25 | 23 | 23
Amounts received | (19) | (19) | (18)
Ending Balance | 171 | 165 | 161
Cemig geracao camargos s.a. [member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 124 | 120 |
Monetary updating | 18 | 17 | 17
Amounts received | (14) | (13) | (13)
Ending Balance | 128 | 124 | 120
Cemig geracao sul s.a. [member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 161 | 157 |
Monetary updating | 26 | 24 | 24
Amounts received | (20) | (20) | (19)
Ending Balance | 167 | 161 | 157
Cemig geracao leste s.a. [member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 110 | 107 |
Monetary updating | 19 | 18 | 18
Amounts received | (15) | (15) | (14)
Ending Balance | 114 | 110 | 107
Cemig geracao oeste s.a. [member] |  |  |
Disclosure Of Financial Assets and Liabilities Of The Concession [line items] |  |  |
Beginning Balance | 66 | 64 |
Monetary updating | 12 | 12 | 11
Amounts received | (9) | (9) | (10)
Ending Balance | R$ 69 | R$ 66 | R$ 64

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