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14. FINANCIAL INSTRUMENTS (Details 14) - BRL (R$) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of detailed information about financial instruments [line items] |  |  |
Movement | R$ 5,537,174 | R$ 604,828 | R$ 1,415,962
Realization | (1,667,886) | (790,353) | R$ (370,191)
Foreign exchange risk [member] | Cash flow hedge accounting platts [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Change in the amounts related to cash flow hedge |  |  |
Movement | (283,974) |  |
Realization | (283,149) |  |
Change in the amounts related to cash flow hedge | 825 |  |
Foreign exchange risk [member] | Income tax and social contribution on cash flow hedge accounting [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Change in the amounts related to cash flow hedge |  |  |
Movement | 96,551 |  |
Realization | 96,271 |  |
Change in the amounts related to cash flow hedge | (280) |  |
Foreign exchange risk [member] | Fair value of cash flow accounting platts net [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Change in the amounts related to cash flow hedge |  |  |
Movement | (187,423) |  |
Realization | (186,878) |  |
Change in the amounts related to cash flow hedge | R$ 545 |  |

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