XML 224 R172.htm IDEA: XBRL DOCUMENT v3.19.1

Post-employment Benefits - Summary of Main Assumptions Used in Actuarial Valuation of Retirement Plans (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2018
Disclosure of defined benefit plans [abstract]
Increase in probabilities of survival	10.00%

X

- References

No definition available.

+ Details

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

X

- Definition

Percentage of Increase in Probabilities of Survival

+ References

No definition available.

+ Details

Name:	itub_PercentageOfIncreaseInProbabilitiesOfSurvival
Namespace Prefix:	itub_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration