Allowance for Credit Losses - Effect of loan and leases modifications (Details) $ in Thousands	12 Months Ended
Mar. 31, 2026 USD ($)
Effect of loan and lease modifications
Principal Forgiveness	$ 107
Weighted-Average Interest Rate Reduction	1.25%
Weighted-Average Term Extension	72 months
Residential \| First Liens
Effect of loan and lease modifications
Principal Forgiveness	$ 100
Weighted-Average Interest Rate Reduction	1.53%
Residential \| Junior Liens
Effect of loan and lease modifications
Principal Forgiveness	$ 99
Weighted-Average Interest Rate Reduction	1.25%
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	$ 107
Weighted-Average Interest Rate Reduction	1.27%
Weighted-Average Term Extension	22 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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