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Concession Financial and Sector Assets and Liabilities - Schedule of Changes in Concession Financial Assets (Details) - BRL (R$) R$ in Millions |  | 12 Months Ended
--- | --- | ---
Jul. 20, 2023 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
IfrsStatementLineItems [Line Items] |  |  |  |
Beginning balance |  | R$ 5,993 |  |
Amounts received | R$ 47 | (331) | R$ (309) | R$ (281)
Ending balance |  | 6,540 | 5,993 |
Assets related to infrastructure [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Beginning balance |  | 5,049 |  |
Ending balance |  | 5,735 | 5,049 |
Infrastructure [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Beginning balance |  | 5,049 | 4,326 | 3,924
Transfers from contract assets |  | 363 | 670 | 110
Transfers from (to) intangible assets |  |  | (22) | (9)
Monetary updating |  |  | 556 | 582
Fair Value Adjustments |  |  | (172) |
Disposals |  | 654 | (1) | (1)
Amounts received |  | (331) | (308) | (280)
Ending balance |  | 5,735 | 5,049 | 4,326
Energy Distribution [Member] | Infrastructure [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Beginning balance |  | 1,370 | 684 | 530
Transfers from contract assets |  | 363 | 670 | 110
Transfers from (to) intangible assets |  |  | (22) | (9)
Monetary updating |  |  | 39 | 54
Disposals |  | 148 | (1) | (1)
Ending balance |  | 1,881 | 1,370 | 684
Generation [member] | Infrastructure [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Beginning balance |  | 3,642 | 3,608 | 3,365
Monetary updating |  |  | 514 | 523
Fair Value Adjustments |  |  | (172) |
Disposals |  | 505 |  |
Amounts received |  | (331) | (308) | (280)
Ending balance |  | 3,816 | 3,642 | 3,608
Gas Distribution [Member] | Infrastructure [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Beginning balance |  | 37 | 34 | 29
Monetary updating |  |  | 3 | 5
Disposals |  | 1 |  |
Ending balance |  | R$ 38 | R$ 37 | R$ 34

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