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Financial Instruments and Risk Management - Schedule of Exchange Rate Risk (Details) - BRL (R$) R$ in Millions | Dec. 31, 2023 | Dec. 31, 2022
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Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | R$ (2,097) | R$ (4,249)
Foreign Currency Risk [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (434) | (814)
Local Currency [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (2,097) | (4,249)
Loan [Member] | Foreign Currency Risk [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (384) | (762)
Loan [Member] | Local Currency [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (1,857) | (3,975)
Suppliers (itaipu binacional) [member] | Foreign Currency Risk [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | (50) | (52)
Suppliers (itaipu binacional) [member] | Local Currency [Member] |  |
Disclosure of financial liabilities [line items] |  |
Net liabilities exposed | R$ (240) | R$ (274)

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