Hedge accounting (Details 5) - BRL (R$)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
IfrsStatementLineItems [Line Items]
Credit derivative, nominal amount	R$ 273,280,000,000	R$ 148,125,000,000
Hedging instrument, assets	4,556,000,000	7,061,000,000
Hedging instrument, liabilities	1,965,000,000	3,748,000,000
Gain (loss) on hedge ineffectiveness recognised in profit or loss	(160,000,000)	(19,000,000)
Fair value hedges [member]
IfrsStatementLineItems [Line Items]
Credit derivative, nominal amount	37,951,000,000	22,826,000,000
Fair value hedges [member] \| Interest rate risk [member]
IfrsStatementLineItems [Line Items]
Credit derivative, nominal amount	37,951,000,000	22,826,000,000
Hedging instrument, assets	1,006,000,000	2,000,000
Hedging instrument, liabilities	929,000,000	551,000,000
Gain (loss) on change in fair value of hedging instrument used as basis for recognising hedge ineffectiveness	(30,000,000)	(387,000,000)
Gain (loss) on hedge ineffectiveness recognised in profit or loss	(10,000,000)	(4,000,000)
Fair value hedges [member] \| Interest rate risk [member] \| Interest rate swap2 [Member]
IfrsStatementLineItems [Line Items]
Credit derivative, nominal amount	35,091,000,000	22,826,000,000
Hedging instrument, assets	1,002,000,000	2,000,000
Hedging instrument, liabilities	929,000,000	551,000,000
Gain (loss) on change in fair value of hedging instrument used as basis for recognising hedge ineffectiveness	(49,000,000)	(387,000,000)
Gain (loss) on hedge ineffectiveness recognised in profit or loss	(10,000,000)	R$ (4,000,000)
Fair value hedges [member] \| Interest rate risk [member] \| Interest rate futures [member]
IfrsStatementLineItems [Line Items]
Credit derivative, nominal amount	2,860,000,000
Hedging instrument, assets	4,000,000
Hedging instrument, liabilities
Gain (loss) on change in fair value of hedging instrument used as basis for recognising hedge ineffectiveness	19,000,000
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 2022-03-24
-Paragraph 24G
-Subparagraph a
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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 2022-03-24
-Paragraph 24A
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_24A_c&doctype=Standard
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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
-IssueDate 2022-03-24
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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The amount of a hedging instrument, recognised as an asset. [Refer: Hedging instruments [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 24A
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The amount of a hedging instrument, recognised as a liability. [Refer: Hedging instruments [member]]

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