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v3.19.1

Insurance Contracts and Private Pension - Summary of Main Insurance lines (Detail) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Group accident insurance [Member] |  |
Disclosure of Types of Insurance Contracts [Line Items] |  |
Sales ratio | 34.30% | 38.00%
Loss ratio | 9.40% | 7.80%
Individual accident [Member] |  |
Disclosure of Types of Insurance Contracts [Line Items] |  |
Sales ratio | 14.10% | 12.50%
Loss ratio | 20.80% | 23.50%
Commercial Multiple Peril [Member] |  |
Disclosure of Types of Insurance Contracts [Line Items] |  |
Sales ratio | 21.10% | 21.20%
Loss ratio | 29.30% | 36.40%
Internal Credit [Member] |  |
Disclosure of Types of Insurance Contracts [Line Items] |  |
Sales ratio | 0.70% | 0.90%
Loss ratio | 134.50% | 139.60%
Mandatory personal injury caused by motor vehicle [Member] |  |
Disclosure of Types of Insurance Contracts [Line Items] |  |
Sales ratio |  | 1.20%
Loss ratio |  | 84.50%
Serious or Terminal Diseases [Member] |  |
Disclosure of Types of Insurance Contracts [Line Items] |  |
Sales ratio | 16.10% | 10.70%
Loss ratio | 17.50% | 21.10%
Extended Warranty Assets [Member] |  |
Disclosure of Types of Insurance Contracts [Line Items] |  |
Sales ratio | 62.00% | 62.10%
Loss ratio | 13.90% | 16.00%
Credit Life [Member] |  |
Disclosure of Types of Insurance Contracts [Line Items] |  |
Sales ratio | 20.40% | 18.70%
Loss ratio | 18.30% | 16.90%
Income from Uncertain Events [member] |  |
Disclosure of Types of Insurance Contracts [Line Items] |  |
Sales ratio | 20.30% | 16.30%
Loss ratio | 17.10% | 18.40%
Multiple Risks [Member] |  |
Disclosure of Types of Insurance Contracts [Line Items] |  |
Sales ratio | 48.10% | 57.80%
Loss ratio | 53.30% | 27.20%
Home insurance in market policies credit life [Member] |  |
Disclosure of Types of Insurance Contracts [Line Items] |  |
Sales ratio | 20.40% | 20.70%
Loss ratio | 15.30% | 13.00%
Group life [Member] |  |
Disclosure of Types of Insurance Contracts [Line Items] |  |
Sales ratio | 15.10% | 8.30%
Loss ratio | 33.20% | 24.20%

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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
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- Definition Insurance loss ratio. + References No definition available. + Details
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- Definition Insurance sales ratio. + References No definition available. + Details
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- Details
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- Details
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- Details
Name: | ifrs-full_TypesOfInsuranceContractsAxis=itub_CommercialMultiplePerilMember
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Data Type: | na
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- Details
Name: | ifrs-full_TypesOfInsuranceContractsAxis=itub_InternalCreditMember
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Data Type: | na
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- Details
Name: | ifrs-full_TypesOfInsuranceContractsAxis=itub_MandatoryInsuranceForPersonalInjuryCausedByMotorVehiclesMember
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Data Type: | na
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- Details
Name: | ifrs-full_TypesOfInsuranceContractsAxis=itub_SeriousOrTerminalDiseasesMember
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Data Type: | na
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- Details
Name: | ifrs-full_TypesOfInsuranceContractsAxis=itub_ExtendedWarrantyAssetsMember
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Data Type: | na
Balance Type: |
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- Details
Name: | ifrs-full_TypesOfInsuranceContractsAxis=itub_CreditLifeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
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- Details
Name: | ifrs-full_TypesOfInsuranceContractsAxis=itub_IncomeFromUncertainEventsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
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- Details
Name: | ifrs-full_TypesOfInsuranceContractsAxis=itub_MultipleRisksMember
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- Details
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- Details
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Balance Type: |
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