Borrowings - Additional Information (Details) - USD ($)	Dec. 31, 2024	Mar. 31, 2024
Line of Credit Facility [Line Items]
Outstanding borrowings	$ 0	$ 0
Remaining availability for FHLB borrowings	40,500,000	40,100,000
Investment Securities Pledged
Line of Credit Facility [Line Items]
FHLB borrowings, collateral for advances	51,000
Loans Pledged
Line of Credit Facility [Line Items]
FHLB borrowings, collateral for advances	54,000,000
Private Bankers' Bank
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	$ 5,000,000	$ 5,000,000

Amount of short-term and long-term debt and lease obligation.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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