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Financial Assets Held for Trading and Designated at Fair Value Through Profit or Loss - Summary of Financial Assets Designated at Fair Value Through Profit or Loss (Detail) - BRL (R$) R$ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Jan. 01, 2017
Disclosure of financial assets designated as measured at fair value through profit or loss [Line Items] |  |  |
Fair value | R$ 286,646 | R$ 273,536 | R$ 218,805
Financial assets at fair value through profit or loss, designated upon initial recognition or subsequently, category [member] |  |  |
Disclosure of financial assets designated as measured at fair value through profit or loss [Line Items] |  |  |
Gross carrying amount | 1,232 | 1,670 |
Accumulated gain / (loss) reflected in income | 37 | 76 |
Fair value | 1,269 | 1,746 |
Financial assets at fair value through profit or loss, designated upon initial recognition or subsequently, category [member] | Brazilian external debt bonds [Member] |  |  |
Disclosure of financial assets designated as measured at fair value through profit or loss [Line Items] |  |  |
Gross carrying amount | 1,232 | 1,670 |
Accumulated gain / (loss) reflected in income | 37 | 76 |
Fair value | R$ 1,269 | R$ 1,746 |

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- Definition The amount of financial assets that are measured at fair value and for which gains (losses) are recognised in profit or loss. A financial asset shall be measured at fair value through profit or loss unless it is measured at amortised cost or at fair value through other comprehensive income. A gain (loss) on a financial asset measured at fair value shall be recognised in profit or loss unless it is part of a hedging relationship, it is an investment in an equity instrument for which the entity has elected to present gains and losses in other comprehensive income or it is a financial asset measured at fair value through other comprehensive income. [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 8 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_8_a&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The gains (losses) on financial assets at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 20 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_20_a_i&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition Disclosure of financial assets designated as measured at fair value through profit or loss. + References No definition available. + Details
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- Definition Financial assets at cost through profit or loss. + References No definition available. + Details
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