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Investment Securities-Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Jun. 30, 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	$ 1,678
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	4,680
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	22,611
Debt Securities, Available-for-sale, Amortized Cost	59,913	$ 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	1,669
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	3,984
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	17,203
Available-for-sale	$ 46,945	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	6.58%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate	2.44%
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate	3.39%
Available-for-sale Securities, Debt Maturities, Weighted Average Rate	2.52%
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount
Held-to-maturity	$ 1,940	2,008
Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity
Held-to-maturity, Fair Value	$ 1,839	$ 1,905

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