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v3.20.1

Risk and Capital Management - Summary of Risks of Insurance and Private Pension (Detail) - ITAU UNIBANCO HOLDING [Member] - BRL (R$) | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Mandatory personal injury caused by motor vehicle [Member] |  |  |
Disclosure of insurance risk [Line Items] |  |  |
Insurance premiums | R$ 0 |  | R$ 24,000,000
Retained premium | R$ 0 |  | R$ 24
Retention | 0.00% | 0.00% | 100.00%
Group accident insurance [Member] |  |  |
Disclosure of insurance risk [Line Items] |  |  |
Insurance premiums | R$ 867,000,000 | R$ 690,000,000 | R$ 667,000,000
Retained premium | R$ 867,000,000 | R$ 689,000,000 | R$ 666,000,000
Retention | 100.00% | 99.90% | 99.80%
Individual accident [Member] |  |  |
Disclosure of insurance risk [Line Items] |  |  |
Insurance premiums | R$ 222,000,000 | R$ 275,000,000 | R$ 290,000,000
Retained premium | R$ 222,000,000 | R$ 280,000,000 | R$ 289,000,000
Retention | 100.00% | 101.80% | 99.80%
Home insurance in market policies credit life [Member] |  |  |
Disclosure of insurance risk [Line Items] |  |  |
Insurance premiums | R$ 948,000,000 | R$ 881,000,000 | R$ 623,000,000
Retained premium | R$ 946,000,000 | R$ 879,000,000 | R$ 621,000,000
Retention | 99.80% | 99.80% | 99.70%
Group life [Member] |  |  |
Disclosure of insurance risk [Line Items] |  |  |
Insurance premiums | R$ 948,000,000 | R$ 934,000,000 | R$ 1,001,000,000
Retained premium | R$ 947,000,000 | R$ 937,000,000 | R$ 990,000,000
Retention | 99.90% | 100.30% | 98.90%

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- Definition Line items represents insurance risk. + References No definition available. + Details
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- Definition Reinsurance Premium. + References No definition available. + Details
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- Definition Retained premiums. + References No definition available. + Details
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- Definition Retention Percentage + References No definition available. + Details
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- Details
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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
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- Details
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Balance Type: |
Period Type: |

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- Details
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- Details
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- Details
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Period Type: |