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Loan and Lease Operations Portfolio - Summary of Reconciliation of Expected Loan Losses for Loan Operations and Lease Operations (Parenthetical) (Detail) - BRL (R$) R$ in Millions | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of loans and lease operations [Abstract] |  |  |
Expected loan losses for financial guarantees pledged | R$ (837) | R$ (1,191) | R$ (1,907)
Commitments released | R$ (3,303) | R$ (2,601) | R$ (3,015)

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- Definition Expected loan losses for financial guarantees pledged. + References No definition available. + Details
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