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10. INCOME AND SOCIAL CONTRIBUTION TAXES (Details 3) R$ in Millions | Dec. 31, 2020 BRL (R$)
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Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |
Deferred tax assets future taxable profits | R$ 4,323
2021 [member] |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |
Deferred tax assets future taxable profits | 681
2021 [member] |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |
Deferred tax assets future taxable profits | 708
2025 [member] |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |
Deferred tax assets future taxable profits | 624
2023 [member] |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |
Deferred tax assets future taxable profits | 563
2024 [member] |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |
Deferred tax assets future taxable profits | 563
2026 to 2028 [member] |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |
Deferred tax assets future taxable profits | 743
2029 to 2030 [member] |
Disclosure Of Future Taxable Profits Enable Deferred Tax Assets [line items] |
Deferred tax assets future taxable profits | R$ 441

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