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v3.19.1

Taxes - Summary of Calculation of Tax Rates (Parenthetical) (Detail) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Disclosure of effective income tax rate [Line Items] |  |
Social contribution of tax rate | 20.00% | 15.00%
Financial institutions [member] | Bottom of range [member] |  |
Disclosure of effective income tax rate [Line Items] |  |
Social contribution of tax rate | 15.00% |
Financial institutions [member] | Top of range [member] |  |
Disclosure of effective income tax rate [Line Items] |  |
Social contribution of tax rate | 20.00% |
Other companies [member] |  |
Disclosure of effective income tax rate [Line Items] |  |
Social contribution of tax rate | 9.00% |

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- Definition Line items represent effective income tax rate. + References No definition available. + Details
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- Definition Social contribution tax rate. + References No definition available. + Details
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- Details
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- Details
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