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2. BASIS OF PREPARATION (Details 3) - BRL (R$) R$ in Millions |  |  | 12 Months Ended
--- | --- | --- | ---
Apr. 30, 2021 | Jan. 02, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
BasisOfPreparationLineItems [Line Items] |  |  |  |  |  |  |  |  |
NET INCOME FOR THE YEAR |  | R$ 2,864 |  |  | R$ 2,865 | R$ 3,194 | [1] | R$ 1,764 | [1]
OTHER COMPREHENSIVE INCOME |  |  |  |  |  |  |  |  |
COMPREHENSIVE INCOME FOR THE YEAR |  |  |  |  | 2,858 |  |  |  |
Total of comprehensive income for the year attributed to: |  |  |  |  |  |  |  |  |
Equity holders of the parent |  |  |  |  | 2,857 |  |  |  |
Non-controlling interests |  |  |  |  | 1 |  |  |  |
COMPREHENSIVE INCOME FOR THE YEAR |  |  |  |  | R$ 2,858 |  |  |  |
As presented [member] |  |  |  |  |  |  |  |  |
BasisOfPreparationLineItems [Line Items] |  |  |  |  |  |  |  |  |
NET INCOME FOR THE YEAR |  |  | R$ 1,742 |  |  | 3,128 |  | 1,742 |
OTHER COMPREHENSIVE INCOME |  |  |  |  |  |  |  |  |
Items not to be reclassified to profit or loss in subsequent periods |  |  |  |  |  | (1,055) |  | (463) |
COMPREHENSIVE INCOME FOR THE YEAR |  |  |  |  |  | 2,073 |  | 1,279 |
Total of comprehensive income for the year attributed to: |  |  |  |  |  |  |  |  |
Equity holders of the parent |  |  |  |  |  | 2,072 |  | 1,237 |
Non-controlling interests |  |  |  |  |  | 1 |  | 42 |
COMPREHENSIVE INCOME FOR THE YEAR |  |  |  |  |  | 2,073 |  | 1,279 |
Adjustment [member] |  |  |  |  |  |  |  |  |
BasisOfPreparationLineItems [Line Items] |  |  |  |  |  |  |  |  |
NET INCOME FOR THE YEAR |  |  | 22 |  |  | 65 |  | 22 |
OTHER COMPREHENSIVE INCOME |  |  |  |  |  |  |  |  |
Items not to be reclassified to profit or loss in subsequent periods |  |  |  |  |  |  |  |  |
COMPREHENSIVE INCOME FOR THE YEAR |  |  |  |  |  | 67 |  | 22 |
Total of comprehensive income for the year attributed to: |  |  |  |  |  |  |  |  |
Equity holders of the parent |  |  |  |  |  | 66 |  | 22 |
Non-controlling interests |  |  |  |  |  |  |  |  |
COMPREHENSIVE INCOME FOR THE YEAR |  |  |  |  |  | 67 |  | 22 |
Restated [member] |  |  |  |  |  |  |  |  |
BasisOfPreparationLineItems [Line Items] |  |  |  |  |  |  |  |  |
NET INCOME FOR THE YEAR |  |  | R$ 1,764 | [1] |  | 3,195 | [2] | 1,764 | [2]
OTHER COMPREHENSIVE INCOME |  |  |  |  |  |  |  |  |
Items not to be reclassified to profit or loss in subsequent periods |  |  |  |  |  | (1,055) |  | (463) |
COMPREHENSIVE INCOME FOR THE YEAR | [2] |  |  |  |  | 2,140 |  | 1,301 |
Total of comprehensive income for the year attributed to: |  |  |  |  |  |  |  |  |
Equity holders of the parent | [2] |  |  |  |  | 2,139 |  | 1,259 |
Non-controlling interests | [2] |  |  |  |  | 1 |  | 42 |
COMPREHENSIVE INCOME FOR THE YEAR | [2] |  |  |  |  | R$ 2,140 |  | R$ 1,301 |
[1] | See note 2.8.
[2] | For further details of restatement of comparative balances, see Note 2.8

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