Post-employment benefits (Details 3) - BRL (R$) R$ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
IfrsStatementLineItems [Line Items]
Estimated contribution	R$ 111
Contributions made	523	R$ 160
Fundacao Itau Unibanco Previdencia Complementar [Member]
IfrsStatementLineItems [Line Items]
Estimated contribution	17
Contributions made	70	69
Funbep Fundo De Pensao Multipatrocinado [Member]
IfrsStatementLineItems [Line Items]
Estimated contribution	94
Contributions made	R$ 453	R$ 91

The estimate of the expected contributions to be made to a defined benefit plan for the next annual reporting period. [Refer: Defined benefit plans [domain]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 147
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_147_b&doctype=Standard
-URIDate 2024-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 148
-Subparagraph d
-Clause iii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_148_d_iii&doctype=Standard
-URIDate 2024-03-27

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration