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Investment Securities-Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Mar. 31, 2024
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	$ 952
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	4,673
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	21,777
Debt Securities, Available-for-sale, Amortized Cost	57,118	$ 60,735
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	945
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	3,954
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	16,225
Available-for-sale	$ 44,121	48,030
Available-for-Sale Securities, Debt Maturities, Weighted Average Yield
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Weighted Average Rate	5.83%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate	2.45%
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate	3.10%
Available-for-sale Securities, Debt Maturities, Weighted Average Rate	2.34%
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount
Held-to-maturity	$ 1,807	2,008
Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity
Held-to-maturity, Fair Value	$ 1,735	$ 1,905

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