XML 251 R199.htm IDEA: XBRL DOCUMENT v3.19.1

Contingent Assets and Liabilities, Provisions and Legal Obligations - Summary of Assets Pledged as Collateral for Lawsuits Involving Contingent Liabilities are Restricted or Deposited (Detail) - Guarantees Of Contingencies Provisions And Legal Obligations [Member] - BRL (R$) R$ in Millions	Dec. 31, 2018	Dec. 31, 2017
Disclosure of contingent liabilities [line items]
Financial assets - at fair value through profit or loss and at fair value through other comprehensive income (basically financial treasury bills)	R$ 730	R$ 962
Escrow deposits	R$ 4,312	R$ 4,585

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfContingentLiabilitiesLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

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- Definition

The fair value of financial assets. [Refer: At fair value [member]; Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 25
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_25&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_FinancialAssetsAtFairValue
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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- Definition

Escrow deposit.

+ References

No definition available.

+ Details

Name:	itub_EscrowDeposit1
Namespace Prefix:	itub_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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- Details

Name:	ifrs-full_ItemsOfContingentLiabilitiesAxis=itub_GuaranteesOfContingenciesProvisionsAndLegalObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: