XML 279 R117.htm IDEA: XBRL DOCUMENT v3.20.1

Loan and Lease Operations Portfolio - Summary of Reconciliation of Expected Loan Losses for Loan Operations and Lease Operations (Parenthetical) (Detail) - BRL (R$) R$ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of loans and lease operations [Abstract]
Expected loan losses for financial guarantees pledged	R$ (837)	R$ (1,191)	R$ (1,907)
Commitments released	R$ (3,303)	R$ (2,601)	R$ (3,015)

X

- Definition

Disclosure of loans and lease operations.

+ References

No definition available.

+ Details

Name:	itub_DisclosureOfLoansAndLeaseOperationsAbstract
Namespace Prefix:	itub_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Expected loan losses commitments released

+ References

No definition available.

+ Details

Name:	itub_ExpectedLoanLossesCommitmentsReleased
Namespace Prefix:	itub_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Expected loan losses for financial guarantees pledged.

+ References

No definition available.

+ Details

Name:	itub_ExpectedLoanLossesForFinancialGuaranteesPledged
Namespace Prefix:	itub_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration