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14. CONCESSION FINANCIAL AND SECTOR ASSETS AND LIABILITIES (Details 1) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of financial assets [line items] |  |  |
Amounts received | R$ (265) | R$ (250) | R$ (250)
Monetary updating | 347 | 317 | 322
Restated [member] |  |  |
Disclosure of financial assets [line items] |  |  |
Beginning Balance |  | 3,621 | 7,084
Effects of first-time adoption of IFRS 15 (Restated) |  |  | (2,475)
Amounts received |  |  | (1,389)
Others transfers |  |  | (2)
Ending Balance |  |  | 3,621
Infrastructure [member] |  |  |
Disclosure of financial assets [line items] |  |  |
Beginning Balance | 3,768 | 3,621 |
Amounts received | (266) |  |
Transfers from contract assets | 60 | 48 |
Transfers from (to) intangible assets | (5) | 23 |
Monetary updating | 367 | 336 | 377
Disposals |  | (1) | (1)
Transfers from PP&E |  |  | 27
Ending Balance | 3,924 | 3,768 | 3,621
Infrastructure [member] | Restated [member] |  |  |
Disclosure of financial assets [line items] |  |  |
Beginning Balance | 3,768 | 3,621 |
Amounts received |  | (259) |
Ending Balance |  | 3,768 | 3,621
Infrastructure [member] | Transmission [member] |  |  |
Disclosure of financial assets [line items] |  |  |
Beginning Balance |  |  |
Amounts received |  |  |
Transfers from contract assets |  |  |
Transfers from (to) intangible assets |  |  |
Monetary updating |  |  |
Disposals |  |  |
Transfers from PP&E |  |  |
Ending Balance |  |  |
Infrastructure [member] | Transmission [member] | Restated [member] |  |  |
Disclosure of financial assets [line items] |  |  |
Beginning Balance |  |  | 2,475
Effects of first-time adoption of IFRS 15 (Restated) |  |  | (2,475)
Amounts received |  |  |
Others transfers |  |  |
Ending Balance |  |  |
Infrastructure [member] | Generation [member] |  |  |
Disclosure of financial assets [line items] |  |  |
Beginning Balance | 3,284 | 3,225 |
Amounts received | (266) |  |
Transfers from contract assets |  |  |
Transfers from (to) intangible assets |  |  |
Monetary updating | 347 | 318 | 377
Disposals |  |  |
Transfers from PP&E |  |  |
Ending Balance | 3,365 | 3,284 | 3,225
Infrastructure [member] | Generation [member] | Restated [member] |  |  |
Disclosure of financial assets [line items] |  |  |
Beginning Balance | 3,284 | 3,225 | 4,238
Effects of first-time adoption of IFRS 15 (Restated) |  |  |
Amounts received |  | (259) | (1,389)
Others transfers |  |  | (1)
Ending Balance |  | 3,284 | 3,225
Infrastructure [member] | Distribution [member] |  |  |
Disclosure of financial assets [line items] |  |  |
Beginning Balance | 460 | 396 |
Amounts received |  |  |
Transfers from contract assets | 60 | 48 |
Transfers from (to) intangible assets | (5) | (1) |
Monetary updating | 15 | 18 |
Disposals |  | (1) | (1)
Transfers from PP&E |  |  | 27
Ending Balance | 530 | 460 | 396
Infrastructure [member] | Distribution [member] | Restated [member] |  |  |
Disclosure of financial assets [line items] |  |  |
Beginning Balance | 460 | 396 | 371
Effects of first-time adoption of IFRS 15 (Restated) |  |  |
Amounts received |  |  |
Others transfers |  |  | (1)
Ending Balance |  | 460 | 396
Infrastructure [member] | Gas [member] |  |  |
Disclosure of financial assets [line items] |  |  |
Beginning Balance | 24 |  |
Amounts received |  |  |
Transfers from contract assets |  |  |
Transfers from (to) intangible assets |  | 24 |
Monetary updating | 5 |  |
Disposals |  |  |
Transfers from PP&E |  |  |
Ending Balance | 29 | 24 |
Infrastructure [member] | Gas [member] | Restated [member] |  |  |
Disclosure of financial assets [line items] |  |  |
Beginning Balance | R$ 24 |  |
Effects of first-time adoption of IFRS 15 (Restated) |  |  |
Amounts received |  |  |
Others transfers |  |  |
Ending Balance |  | R$ 24 |

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