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Loan Operations and Lease Operations Portfolio - Summary of Loan Operations and Lease Operations by Type (Parenthetical) (Detail) - BRL (R$) R$ in Millions |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
Dec. 31, 2018 | Jan. 01, 2018 | Dec. 31, 2017 | Jan. 01, 2017 | Dec. 31, 2016 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of loans and lease operations [Line Items] |  |  |  |  |  |  |
Provision for Expected Loss | R$ (33,373) |  | R$ (36,737) | R$ (36,763) |  | R$ (33,373) | R$ (36,737)
Commitments released | (2,601) | R$ (3,015) | (3,015) | R$ (2,691) | R$ (2,691) | (2,601) | (3,015)
Financial guarantees pledged [member] |  |  |  |  |  |  |
Disclosure of loans and lease operations [Line Items] |  |  |  |  |  |  |
Provision for Expected Loss | R$ (1,191) |  | R$ (1,907) |  |  | R$ (1,191) | R$ (1,907)

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- Definition The amount of an allowance account used to record impairments to financial assets due to credit losses. [Refer: Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2018-01-01 -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 16 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_16&doctype=Standard&book=B -URIDate 2017-03-09 + Details
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- Definition Disclosure of loans and lease operations + References No definition available. + Details
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- Definition Expected loan losses commitments released + References No definition available. + Details
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- Details
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