Loans (Tier Risk Rating System) - Additional Information (Detail)	3 Months Ended
Mar. 31, 2022
Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Repayment period of loan with a reasonable reduction of principal balance	2 years

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration