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Investment Securities-Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Mar. 31, 2025
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	$ 528
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	15,155
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	11,185
Debt Securities, Available-for-sale, Amortized Cost	55,076	$ 56,475
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	524
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	12,765
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	8,210
Available-for-sale	$ 44,069	44,522
Available-for-Sale Securities, Debt Maturities, Weighted Average Yield
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Weighted Average Rate	5.63%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate	2.27%
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate	3.90%
Available-for-sale Securities, Debt Maturities, Weighted Average Rate	2.29%
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount
Held-to-maturity	$ 1,650	1,750
Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity
Held-to-maturity, Fair Value	$ 1,619	$ 1,698

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