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33. FINANCIAL INSTRUMENTS AND RISK MANAGEMENT (Details 7) - 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
Net effect of exchange rate fluctuation |  |
United States of America, Dollars | Probable Scenario [Member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 8,196 |
Net effect of exchange rate fluctuation | 1,843 |
United States of America, Dollars | Probable Scenario [Member] | Appreciation of Twenty Five Percentage On Brazil Real [Member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 10,245 |
Net effect of exchange rate fluctuation | 3,892 |
United States of America, Dollars | Probable Scenario [Member] | Appreciation of fifty percentage on brazil real [member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 12,294 |
Net effect of exchange rate fluctuation | 5,941 |
United States of America, Dollars | Itaipu Binacional [Member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 243 | 268
United States of America, Dollars | Itaipu Binacional [Member] | Probable Scenario [Member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 313 |
United States of America, Dollars | Itaipu Binacional [Member] | Probable Scenario [Member] | Appreciation of Twenty Five Percentage On Brazil Real [Member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 392 |
United States of America, Dollars | Itaipu Binacional [Member] | Probable Scenario [Member] | Appreciation of fifty percentage on brazil real [member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 470 |
Loans and financings [Member] | United States of America, Dollars |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 6,110 | R$ 5,882
Loans and financings [Member] | United States of America, Dollars | Probable Scenario [Member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 7,883 |
Loans and financings [Member] | United States of America, Dollars | Probable Scenario [Member] | Appreciation of Twenty Five Percentage On Brazil Real [Member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | 9,853 |
Loans and financings [Member] | United States of America, Dollars | Probable Scenario [Member] | Appreciation of fifty percentage on brazil real [member] |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |
Net liabilities exposed | R$ 11,824 |

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