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Risk and Capital Management - Summary of Breakdown of Indicators of Credit Quality (Parenthetical) (Detail) - BRL (R$) R$ in Millions | Dec. 31, 2018 | Dec. 31, 2017 | Jan. 01, 2017
--- | --- | --- | ---
Disclosure of Credit Quality [Line Items] |  |  |
Loan operations and lease operations portfolio | R$ 536,091 | R$ 497,719 | R$ 494,851
Stage 1 [Member] |  |  |
Disclosure of Credit Quality [Line Items] |  |  |
Loan operations and lease operations portfolio |  | R$ 102 |

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