Minimum Regulatory Capital - Additional Information (Detail)	Sep. 30, 2021
Common Equity Tier One Capital
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Capital conservation buffer	2.50%

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.

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Period Type:	duration