Hedge accounting (Details 5) - BRL (R$) R$ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
IfrsStatementLineItems [Line Items]
Credit derivative, nominal amount	R$ 356,851	R$ 282,444
Currency risk [member]
IfrsStatementLineItems [Line Items]
Credit derivative, nominal amount	19,363	19,208
Fair value hedges [member]
IfrsStatementLineItems [Line Items]
Credit derivative, nominal amount	101,443	54,243
Fair value hedges [member] \| Interest rate risk [member]
IfrsStatementLineItems [Line Items]
Credit derivative, nominal amount	101,443	54,243
Hedging instrument, assets	1,574	956
Hedging instrument, liabilities	737	563
Gain (loss) on change in fair value of hedging instrument used as basis for recognising hedge ineffectiveness	(267)	(318)
Gain (loss) on hedge ineffectiveness recognised in profit or loss	3	9
Fair value hedges [member] \| Interest rate risk [member] \| Interest Rate Swap 2 [Member]
IfrsStatementLineItems [Line Items]
Credit derivative, nominal amount	90,201	45,430
Hedging instrument, assets	1,557	893
Hedging instrument, liabilities	737	563
Gain (loss) on change in fair value of hedging instrument used as basis for recognising hedge ineffectiveness	(328)	(331)
Gain (loss) on hedge ineffectiveness recognised in profit or loss	8	7
Fair value hedges [member] \| Interest rate risk [member] \| Interest Rate Futures [Member]
IfrsStatementLineItems [Line Items]
Credit derivative, nominal amount	10,945	8,568
Hedging instrument, assets	17	62
Hedging instrument, liabilities
Gain (loss) on change in fair value of hedging instrument used as basis for recognising hedge ineffectiveness	39	9
Gain (loss) on hedge ineffectiveness recognised in profit or loss	(5)	2
Fair value hedges [member] \| Currency risk [member] \| Interest Rate Futures [Member]
IfrsStatementLineItems [Line Items]
Credit derivative, nominal amount	297	245
Hedging instrument, assets		1
Hedging instrument, liabilities
Gain (loss) on change in fair value of hedging instrument used as basis for recognising hedge ineffectiveness	22	4
Gain (loss) on hedge ineffectiveness recognised in profit or loss

The nominal amount of a credit derivative. [Refer: Derivatives [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 24G
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- Definition

The gain (loss) on the change in fair value of the hedging instrument used as a basis for recognising hedge ineffectiveness. Hedge ineffectiveness is the extent to which the changes in the fair value or the cash flows of the hedging instrument are greater or less than those on the hedged item.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 24A
-Subparagraph c
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- Definition

The gain (loss) recognised in profit or loss on hedge ineffectiveness. [Refer: Gain (loss) on hedge ineffectiveness]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of a hedging instrument, recognised as an asset. [Refer: Hedging instruments [domain]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
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The amount of a hedging instrument, recognised as a liability. [Refer: Hedging instruments [domain]]

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- References

No definition available.

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