Allowance for Credit Losses - Modified loans with payment default (Details) $ in Thousands	12 Months Ended
Mar. 31, 2026 USD ($)
Allowance for Credit Losses
Modified loans past due period considered in payment default	30 days
Consumer \| Principal Forgiveness
Allowance for Credit Losses
Amount	$ 18
Consumer \| Term Extension
Allowance for Credit Losses
Amount	18
Consumer \| Interest Rate Reduction
Allowance for Credit Losses
Amount	103
Consumer \| Motor Vehicle \| Principal Forgiveness
Allowance for Credit Losses
Amount	18
Consumer \| Motor Vehicle \| Term Extension
Allowance for Credit Losses
Amount	18
Residential \| First Liens \| Interest Rate Reduction
Allowance for Credit Losses
Amount	$ 103

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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