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14. FINANCIAL INSTRUMENTS (Details 13) - 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] |  |  |
Other income and expenses | R$ (5,224,682) | R$ (4,631,236) | R$ 83,332
Other comprehensive income | (3,154,442) | 105,537 | R$ (2,713,844)
Exchange variation | 3,336 |  |
Foreign exchange risk [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Appreciation asset position | 501,066 |  |
Appreciation liability position | (606,430) |  |
Fair value market amoount receivable / payable | (105,364) |  |
Other income and expenses | (283,149) |  |
Other comprehensive income | (825) |  |
Exchange variation | R$ (16,504) |  |
Foreign exchange risk [member] | 09/02/2020 (settled) [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Notional | Platts |  |
Other income and expenses | R$ (31,678) |  |
Exchange variation | R$ (136) |  |
Foreign exchange risk [member] | 10/02/2020 (settled) [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Notional | Platts |  |
Other income and expenses | R$ (132,997) |  |
Exchange variation | R$ (9,051) |  |
Foreign exchange risk [member] | 11/04/2020 (settled) [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Notional | Platts |  |
Other income and expenses | R$ (85,164) |  |
Exchange variation | R$ (7,301) |  |
Foreign exchange risk [member] | 12/02/2020 (settled) [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Notional | Platts |  |
Other income and expenses | R$ (33,310) |  |
Exchange variation | R$ 52 |  |
Foreign exchange risk [member] | 2/2/2021 [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Notional | Platts |  |
Appreciation asset position | R$ 486,852 |  |
Appreciation liability position | (493,925) |  |
Fair value market amoount receivable / payable | (7,073) |  |
Other comprehensive income | (6,888) |  |
Exchange variation | R$ (185) |  |
Foreign exchange risk [member] | Between one and five years [member] |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Notional | Platts |  |
Appreciation asset position | R$ 527,684 |  |
Appreciation liability position | (521,504) |  |
Fair value market amoount receivable / payable | 6,180 |  |
Other comprehensive income | 6,063 |  |
Exchange variation | R$ 117 |  |

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