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Contingent Assets and Liabilities, Provisions and Legal Obligations - Summary of Assets Pledged as Collateral for Lawsuits Involving Contingent Liabilities are Restricted or Deposited (Detail) - Guarantees Of Contingencies Provisions And Legal Obligations [Member] - BRL (R$) R$ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Disclosure of contingent liabilities [line items] |  |
Financial assets - at fair value through profit or loss and at fair value through other comprehensive income (basically financial treasury bills) | R$ 730 | R$ 962
Escrow deposits | R$ 4,312 | R$ 4,585

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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. + References No definition available. + Details
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- Definition The fair value of financial assets. [Refer: At fair value [member]; Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 25 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_25&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition Escrow deposit. + References No definition available. + Details
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