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Financial Assets at Fair Value Through Other Comprehensive Income-Securities - Summary of Equity Instruments at Fair Value Through Other Comprehensive Income-Securities by Maturity (Detail) - BRL (R$) R$ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items] |  |
Gross carrying amount | R$ 77 | R$ 73
Fair Value | 161 | 148
Non-stated maturity [Member] |  |
Disclosure of fair value of investments in equity instruments designated at fair value through other comprehensive income [line items] |  |
Gross carrying amount | 77 | 73
Fair Value | R$ 161 | R$ 148

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- Definition The amount of current investments in equity instruments that the entity has designated at fair value through other comprehensive income. [Refer: Investments in equity instruments designated at fair value through other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2018-01-01 -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 8 -Subparagraph h -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_8_h&doctype=Standard -URIDate 2017-03-09 + Details
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