XML 285 R233.htm IDEA: XBRL DOCUMENT
v3.19.1

Risk and Capital Management - Summary of Assessing Minimum Capital Requirements (Parenthetical) (Detail) | 12 Months Ended
--- | ---
Dec. 31, 2018
Disclosure of regulatory capital [Abstract] |
Capital required for market risk standardized model, percentage | 80.00%

X
- Definition Capital required for market risk standardized model, percentage. + References No definition available. + Details
Name: | itub_CapitalRequiredForMarketRiskStandardizedModelPercentage
Namespace Prefix: | itub_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Disclosure of regulatory capital [Abstract] + References No definition available. + Details
Name: | itub_DisclosureOfRegulatoryCapitalAbstract
Namespace Prefix: | itub_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration