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31. FINANCIAL INSTRUMENTS AND RISK MANAGEMENT (Details 12) - Federal risk [member] | 12 Months Ended
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Dec. 31, 2020
A1 rating [member] |  |
Disclosure of credit risk exposure [line items] |  |
Equity | Over R$ 3.5 billion |
Percentage of limit per bank entity | Between 6% and 9% | [1]
A2 Rating [member] |  |
Disclosure of credit risk exposure [line items] |  |
Equity | R$ 1.0 billion to R$ 3.5 billion |
Percentage of limit per bank entity | Between 5% and 8% | [1]
A3 rating [member] |  |
Disclosure of credit risk exposure [line items] |  |
Equity | R$ 400 to R$ 1.0 billion |
Percentage of limit per bank entity | Between 0% and 7% | [1]
[1] | The percentage assigned to each bank depends on individual assessment of indicators, e.g. liquidity, and quality of the credit portfolio.

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