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33. FINANCIAL INSTRUMENTS AND RISK MANAGEMENT (Details 6) - BRL (R$) R$ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | R$ 6,353 | R$ 6,150
United States of America, Dollars |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 6,353 | 6,150
United States of America, Dollars | Loans and financings [Member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 6,110 | 5,882
United States of America, Dollars | Itaipu Binacional [Member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 243 | 268
Foreign currency risk [Member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 1,576 | 1,588
Foreign currency risk [Member] | Loans and financings [Member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 1,516 | 1,518
Foreign currency risk [Member] | Itaipu Binacional [Member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | R$ 60 | R$ 70

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