XML 103 R156.htm IDEA: XBRL DOCUMENT
v3.20.1

Taxes - Summary of Calculation of Tax Rates (Detail) |  |  | 12 Months Ended
--- | --- | --- | ---
Mar. 01, 2019 | Feb. 28, 2019 | Dec. 31, 2019
Disclosure of effective income tax rate [Abstract] |  |  |
Income tax |  |  | 15.00%
Additional income tax |  |  | 10.00%
Social contribution on net income | 20.00% | 15.00% | 15.00%

X
- Definition Additional income tax rate. + References No definition available. + Details
Name: | itub_AdditionalIncomeTaxRate
Namespace Prefix: | itub_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Disclosure of effective income tax rate. + References No definition available. + Details
Name: | itub_DisclosureOfEffectiveIncomeTaxRateAbstract
Namespace Prefix: | itub_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Income tax rate. + References No definition available. + Details
Name: | itub_IncomeTaxRate
Namespace Prefix: | itub_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Social contribution tax rate. + References No definition available. + Details
Name: | itub_SocialContributionTaxRate
Namespace Prefix: | itub_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration