Allowance for Credit Losses - Effect of loan and leases modifications (Details) $ in Thousands	12 Months Ended
Sep. 30, 2026 USD ($)
Effect of loan and lease modifications
Principal Forgiveness	$ 46
Weighted-Average Interest Rate Reduction	2.03%
Weighted-Average Term Extension	72 months
Residential \| First Liens
Effect of loan and lease modifications
Principal Forgiveness	$ 64
Weighted-Average Interest Rate Reduction	4.25%
Residential \| Junior Liens
Effect of loan and lease modifications
Principal Forgiveness	$ 240
Residential \| All Other Residential
Effect of loan and lease modifications
Weighted-Average Interest Rate Reduction	0.63%
Weighted-Average Term Extension	180 months
Consumer \| Motor Vehicle
Effect of loan and lease modifications
Principal Forgiveness	$ 46
Weighted-Average Term Extension	25 months

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.

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