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14. FINANCIAL INSTRUMENTS (Details 6) R$ in Thousands | 12 Months Ended
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Dec. 31, 2020 BRL (R$)
Probable scenario [member] | USIM3 [member] |
Disclosure of detailed information about financial instruments [line items] |
Sensitivity analysis for stock price risks | R$ (84,064)
Probable scenario [member] | USIM5 [member] |
Disclosure of detailed information about financial instruments [line items] |
Sensitivity analysis for stock price risks | (81,191)
Probable scenario [member] | PATI3 [member] |
Disclosure of detailed information about financial instruments [line items] |
Sensitivity analysis for stock price risks | (2,994)
Scenario 1 [member] | USIM3 [member] |
Disclosure of detailed information about financial instruments [line items] |
Sensitivity analysis for stock price risks | (420,322)
Scenario 1 [member] | USIM5 [member] |
Disclosure of detailed information about financial instruments [line items] |
Sensitivity analysis for stock price risks | (405,955)
Scenario 1 [member] | PATI3 [member] |
Disclosure of detailed information about financial instruments [line items] |
Sensitivity analysis for stock price risks | (14,970)
Scenario 2 [member] | USIM3 [member] |
Disclosure of detailed information about financial instruments [line items] |
Sensitivity analysis for stock price risks | (840,644)
Scenario 2 [member] | USIM5 [member] |
Disclosure of detailed information about financial instruments [line items] |
Sensitivity analysis for stock price risks | (811,910)
Scenario 2 [member] | PATI3 [member] |
Disclosure of detailed information about financial instruments [line items] |
Sensitivity analysis for stock price risks | R$ (29,940)

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