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13. FINANCIAL INSTRUMENTS (Details 15) - BRL (R$) R$ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Perpetual bonds |  |
Disclosure of financial liabilities [line items] |  |
Carrying amount | R$ 3,880,074 | R$ 3,312,503
Fair value | 2,850,615 | 2,602,090
Fixed rate notes |  |
Disclosure of financial liabilities [line items] |  |
Carrying amount | 6,745,132 | 5,751,526
Fair value | R$ 7,595,765 | R$ 6,207,946

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