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Financial Instruments and Risk Management - Schedule of Exchange Rate Risk (Details) - BRL (R$) R$ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | R$ 210 | R$ 2,097
Foreign Currency Risk [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (34) | (434)
Local Currency [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (210) | (2,097)
Loan [Member] | Foreign Currency Risk [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed |  | (384)
Loan [Member] | Local Currency [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed |  | (1,857)
Suppliers (itaipu binacional) [member] | Foreign Currency Risk [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (34) | (50)
Suppliers (itaipu binacional) [member] | Local Currency [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | R$ (210) | R$ (240)

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