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v3.19.1

Risk and Capital Management- Summary of VaR Total - Historical Simulation (Detail) - BRL (R$) R$ in Millions | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | R$ 381.5 | R$ 372.3
Interest rate risk [Member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 898.4 | 764.7
Foreign exchange risk [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 37.3 | 11.9
Shares [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 50.1 | 46.4
Commodity price risk [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 1.0 | 0.8
Risk diversification effect [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | (605.3) | (451.5)
Average [Member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 399.3 | 409.9
Average [Member] | Interest rate risk [Member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 851.4 | 721.0
Average [Member] | Foreign exchange risk [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 24.7 | 20.4
Average [Member] | Shares [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 39.2 | 45.4
Average [Member] | Commodity price risk [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 1.6 | 1.5
Bottom of range [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 294.7 | 304.8
Bottom of range [member] | Interest rate risk [Member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 720.0 | 583.6
Bottom of range [member] | Foreign exchange risk [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 12.7 | 6.5
Bottom of range [member] | Shares [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 23.6 | 38.5
Bottom of range [member] | Commodity price risk [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 0.6 | 0.7
Top of range [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 603.6 | 874.0
Top of range [member] | Interest rate risk [Member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 1,042.9 | 1,311.9
Top of range [member] | Foreign exchange risk [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 45.2 | 50.2
Top of range [member] | Shares [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | 58.5 | 54.9
Top of range [member] | Commodity price risk [member] |  |
Disclosure of Value at Risk historical simulation [Line Items] |  |
Risk factor group | R$ 3.1 | R$ 4.0

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- Definition The measure of a potential loss exposure as a result of future market movements, based on a specified confidence interval and measurement horizon. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 41 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_41&doctype=Standard -URIDate 2017-03-09 + Details
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