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FINANCIAL INSTRUMENTS - Exchange rate risk (Details) - Foreign currency risk - R$ / $ | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019
FINANCIAL INSTRUMENTS |  |
Closing foreign exchange rate | 5.1967 | 4.0307
Percentage of devaluation of Brazilian Real against the U.S. Dollar | 22.44% |

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