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v3.20.1

Risk and Capital Management - Summary of Sensitivity Analysis Impact in Results and Stockholder's Equity (Detail) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of risk management strategy related to hedge accounting [line items] |  |  |
Private Pension | R$ 15,071 | R$ 20,136 | R$ 22,177
5% increase in mortality rates [Member] |  |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |  |
Private Pension | 25 | 15 |
Insurance | 0 |  |
5% decrease in mortality rates [Member] |  |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |  |
Private Pension | (37) | (16) |
Insurance | (1) | (1) |
0.1% increase in risk-free interest rates [Member] |  |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |  |
Private Pension | 61 | 30 |
Insurance | 12 | 8 |
0.1% decrease in risk-free interest rates [Member] |  |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |  |
Private Pension | (63) | (44) |
Insurance | (12) | (8) |
5% increase in conversion in income rates [Member] |  |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |  |
Private Pension | 20 | (14) |
Insurance | 0 |  |
5% decrease in conversion in income rates [Member] |  |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |  |
Private Pension | (21) | 14 |
Insurance | 0 |  |
5% increase in claims [Member] |  |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |  |
Private Pension | 0 |  |
Insurance | (47) | (37) |
5% decrease in claims [Member] |  |  |
Disclosure of risk management strategy related to hedge accounting [line items] |  |  |
Private Pension | 0 |  |
Insurance | R$ 47 | R$ 37 |

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