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11. INCOME AND SOCIAL CONTRIBUTION TAXES (Details 3) - BRL (R$) R$ in Millions | Dec. 31, 2019 | Dec. 31, 2018
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Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |  |
Deferred tax assets future taxable profits | R$ 4,028 | R$ 3,471
2020 [Member] |  |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |  |
Deferred tax assets future taxable profits | 659 |
2021 [Member] |  |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |  |
Deferred tax assets future taxable profits | 571 |
2024 [Member] |  |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |  |
Deferred tax assets future taxable profits | 571 |
2022 [Member] |  |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |  |
Deferred tax assets future taxable profits | 572 |
2023 [Member] |  |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |  |
Deferred tax assets future taxable profits | 571 |
2025 To 2027 [Member] |  |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |  |
Deferred tax assets future taxable profits | 659 |
2028 To 2029 [Member] |  |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |  |
Deferred tax assets future taxable profits | R$ 425 |

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