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Schedule of marketable securities (Details) - BRL (R$) R$ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
IfrsStatementLineItems [Line Items] |  |
Current investments | R$ 1,724 | R$ 3,360
[custom:LongTermSecurities-0] | 354 | 765
[custom:ShortTermAndLongTermSecurities-0] | 2,078 | 4,125
Bank Certificate Of Deposit C D B [Member] |  |
IfrsStatementLineItems [Line Items] |  |
Current investments | 101 | 545
Financial Notes Banks [Member] |  |
IfrsStatementLineItems [Line Items] |  |
Current investments | 1,417 | 2,074
[custom:LongTermSecurities-0] | 348 | 730
Treasury financial notes [member] |  |
IfrsStatementLineItems [Line Items] |  |
Current investments | 178 | 731
Other Investment [Member] |  |
IfrsStatementLineItems [Line Items] |  |
Current investments | 28 | 10
[custom:LongTermSecurities-0] | 1 | 10
Debentures [Member] |  |
IfrsStatementLineItems [Line Items] |  |
[custom:LongTermSecurities-0] | R$ 5 | R$ 25

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