Business Segment Reporting - Additional Information (Details)	Sep. 30, 2020 sector branch
Consumer Bank
Segment Reporting Information [Line Items]
Number of state branch networks \| branch	15
Commercial Bank
Segment Reporting Information [Line Items]
Number of industry sectors \| sector	7

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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