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33. FINANCIAL INSTRUMENTS AND RISK MANAGEMENT (Details 13) - Credit Risk [Member] R$ in Millions | 12 Months Ended
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Dec. 31, 2019 BRL (R$)
A1 Rating [Member] |  |
Disclosure of credit risk exposure [line items] |  |
Bank equity | R$ 3,500 |
Concentration | Minimum of 50% |
A1 Rating [Member] | Bottom Of Range [Member] |  |
Disclosure of credit risk exposure [line items] |  |
Percentage of limit per bank entity | 6.00% | [1]
A1 Rating [Member] | Top of Range [Member] |  |
Disclosure of credit risk exposure [line items] |  |
Percentage of limit per bank entity | 9.00% | [1]
A2 Rating [Member] |  |
Disclosure of credit risk exposure [line items] |  |
Concentration | Maximum 30% |
A2 Rating [Member] | Bottom Of Range [Member] |  |
Disclosure of credit risk exposure [line items] |  |
Bank equity | R$ 100 |
Percentage of limit per bank entity | 5.00% | [1]
A2 Rating [Member] | Top of Range [Member] |  |
Disclosure of credit risk exposure [line items] |  |
Bank equity | R$ 3,500 |
Percentage of limit per bank entity | 8.00% | [1]
B Rating [Member] |  |
Disclosure of credit risk exposure [line items] |  |
Concentration | Maximum 30% |
B Rating [Member] | Bottom Of Range [Member] |  |
Disclosure of credit risk exposure [line items] |  |
Bank equity | R$ 400 |
Percentage of limit per bank entity | 5.00% | [1]
B Rating [Member] | Top of Range [Member] |  |
Disclosure of credit risk exposure [line items] |  |
Bank equity | R$ 100 |
Percentage of limit per bank entity | 7.00% | [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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- Definition The description of a shared characteristic for the concentration of risks arising from financial instruments (for example, counterparty, geographical area, currency or market). [Refer: Financial instruments, class [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2019-01-01 -Paragraph B8 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_B8_b&doctype=Appendix&subtype=B -URIDate 2019-03-27 + Details
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