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Financial Assets at Fair Value Through Profit or Loss - Summary of Financial Assets at Fair Value Through Profit or Loss (Parenthetical) (Detail) - BRL (R$) R$ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Disclosure of financial assets at fair value through profit or loss [line items] |  |
Securities pledged as Guarantee of Funding of Financial Institutions and Clients | R$ 33,848 | R$ 27,469
Brazilian government securities [member] |  |
Disclosure of financial assets at fair value through profit or loss [line items] |  |
Securities pledged as Guarantee of Funding of Financial Institutions and Clients | 24,988 | 26,953
Brazilian government securities [member] | Held-for-trading financial assets [Member] |  |
Disclosure of financial assets at fair value through profit or loss [line items] |  |
Securities pledged as Guarantee of Funding of Financial Institutions and Clients | 30,114 | 30,325
Government securities - abroad [member] |  |
Disclosure of financial assets at fair value through profit or loss [line items] |  |
Securities pledged as Guarantee of Funding of Financial Institutions and Clients |  | 479
Government securities - abroad [member] | Held-for-trading financial assets [Member] |  |
Disclosure of financial assets at fair value through profit or loss [line items] |  |
Securities pledged as Guarantee of Funding of Financial Institutions and Clients | 131 | 46
Corporate securities [member] |  |
Disclosure of financial assets at fair value through profit or loss [line items] |  |
Securities pledged as Guarantee of Funding of Financial Institutions and Clients | 8,860 | 37
Corporate securities [member] | Held-for-trading financial assets [Member] |  |
Disclosure of financial assets at fair value through profit or loss [line items] |  |
Securities pledged as Guarantee of Funding of Financial Institutions and Clients | R$ 30,245 | R$ 30,399

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- Definition The amount of financial assets that the entity has pledged as collateral for liabilities or contingent liabilities, including amounts that have been reclassified in accordance with paragraph 3.2.23(a) of IFRS 9. [Refer: Contingent liabilities [member]; Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 14 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_14_a&doctype=Standard -URIDate 2017-03-09 + Details
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