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Contingent Assets and Liabilities, Provisions and Legal Obligations - Summary of Changes in Civil, Labor and Other Risks Provisions (Parenthetical) (Detail) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Economic Plans [member] |  |
Disclosure of other provisions [line items] |  |
Increase in provision | R$ (184) | R$ 184

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- Definition The amount recognised for new other provisions. [Refer: Other provisions] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 37 -IssueDate 2017-01-01 -Paragraph 84 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=37&date=2017-03-01&anchor=para_84_b&doctype=Standard -URIDate 2017-03-09 + Details
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