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Intangible Assets - Schedule of Composition of Intangible Assets (Details) - BRL (R$) R$ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | --- | ---
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | R$ 16,806 | R$ 15,249 | R$ 14,621 | R$ 12,953
Temporary Easements Intangible Assets [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 7 | 8 | 9 | 10
Onerous Concession [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 3 | 4 | 4 | 5
Assets of Concession [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 15,828 | 14,284 | 13,555 | 11,807
Assets of Concession GSF [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 564 | 697 | 832 | 966
Other Intangible Assets [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 84 | 60 | 15 | 4
Useful Life Defined Intangible Asset [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 16,486 | 15,053 | R$ 14,415 | R$ 12,792
Intangible Assets Under Developments [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 320 | 196 |  |
Historical Cost [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 29,148 | 26,612 |  |
Historical Cost [Member] | Temporary Easements Intangible Assets [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 15 | 15 |  |
Historical Cost [Member] | Onerous Concession [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 14 | 14 |  |
Historical Cost [Member] | Assets of Concession [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 27,594 | 25,217 |  |
Historical Cost [Member] | Assets of Concession GSF [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 1,031 | 1,031 |  |
Historical Cost [Member] | Other Intangible Assets [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 174 | 139 |  |
Historical Cost [Member] | Useful Life Defined Intangible Asset [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 28,828 | 26,416 |  |
Historical Cost [Member] | Intangible Assets Under Developments [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | 320 | 196 |  |
Accumulated depreciation and amortisation [member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | (12,342) | (11,363) |  |
Accumulated depreciation and amortisation [member] | Temporary Easements Intangible Assets [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | (8) | (7) |  |
Accumulated depreciation and amortisation [member] | Onerous Concession [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | (11) | (10) |  |
Accumulated depreciation and amortisation [member] | Assets of Concession [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | (11,766) | (10,933) |  |
Accumulated depreciation and amortisation [member] | Assets of Concession GSF [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | (467) | (334) |  |
Accumulated depreciation and amortisation [member] | Other Intangible Assets [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | (90) | (79) |  |
Accumulated depreciation and amortisation [member] | Useful Life Defined Intangible Asset [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets | (12,342) | (11,363) |  |
Accumulated depreciation and amortisation [member] | Intangible Assets Under Developments [Member] |  |  |  |
IfrsStatementLineItems [Line Items] |  |  |  |
Intangible assets |  |  |  |

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