General and Administrative Expenses - Summary of General and Administrative Expenses (Parenthetical (Detail) R$ in Millions	12 Months Ended
Dec. 31, 2020 BRL (R$)
Analysis of income and expense [abstract]
Donation paid	R$ (1,047)
Impairment Loss Recognized In Profit Or Loss Intangible Assets And Goodwill And Ownership Interest Of Non controlling Interests	R$ (1,452)

Impairment of goodwill and intangible assets of Itaú Corpbanca, net of tax effects and ownership interest of non-controlling shareholders.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration