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Risk and Capital Management - Summary of Financial Assets Individually Evaluated Classified by Rating (Parenthetical) (Detail) - BRL (R$) R$ in Millions | Dec. 31, 2018 | Dec. 31, 2017 | Jan. 01, 2017
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Disclosure of financial assets individually evaluated classified by rating[Abstract] |  |  |
Derivatives | R$ 23,466 | R$ 22,843 | R$ 24,231

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- Definition The amount of financial assets classified as derivative instruments. [Refer: Financial assets; Derivatives [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_55&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition Disclosure of financial assets individually evaluated classified by rating + References No definition available. + Details
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