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Derivatives - Additional Information (Detail) - BRL (R$) R$ in Millions	Dec. 31, 2018	Dec. 31, 2017
Government securities - abroad [member]
Disclosure of Financial Assets [Line Items]
Total value of margins pledged in guarantee	R$ 12,855	R$ 18,284

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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No definition available.

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- Definition

Derivatives pledges as collateral.

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No definition available.

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- Details

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