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Financial Instruments and Risk Management - Schedule Of Fair Value Of Derivative Hedge Instrument One (Details) - BRL (R$) R$ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | R$ 210 | R$ 2,097
Base scenario [member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (210) |
Probable Scenario [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (194) |
Net effect of exchange rate fluctuation | 16 |
Adverse Scenario [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (220) |
Net effect of exchange rate fluctuation | (10) |
Suppliers (itaipu binacional) [member] | Base scenario [member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (210) |
Suppliers (itaipu binacional) [member] | Probable Scenario [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (194) |
Suppliers (itaipu binacional) [member] | Adverse Scenario [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | R$ (220) |

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