Loan and Lease Operations - Summary of Reconciliation of Gross Portfolio of Loan Operations and Lease Operations (Parenthetical) (Detail) - BRL (R$) R$ in Millions	Dec. 31, 2021	Dec. 31, 2020
Disclosure of loans and lease operations [Line Items]
Allowance account for credit losses of financial assets	R$ 41,079	R$ 47,051
London Interbank Offered Rate LIBOR [Member]
Disclosure of loans and lease operations [Line Items]
Allowance account for credit losses of financial assets	R$ 29,875	R$ 40,454

The amount of an allowance account used to record impairments to financial assets due to credit losses. [Refer: Financial assets]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2023-01-01
-Name IFRS
-Number 7
-IssueDate 2021-01-01
-Paragraph 16
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_16&doctype=Standard&book=b
-URIDate 2021-03-24

Name:	ifrs-full_AllowanceAccountForCreditLossesOfFinancialAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant