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Investment Securities-Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Mar. 31, 2022
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	$ 101
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	6,344
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	27,399
Debt Securities, Available-for-sale, Amortized Cost	68,761	$ 74,258
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	99
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	5,965
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	21,035
Available-for-sale	$ 55,041	67,596
Available-for-Sale Securities, Debt Maturities, Weighted Average Yield
Available-for-sale, Securities, Debt Maturities, within One Year, Weighted Average Rate	(0.85%)
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Weighted Average Rate	0.00%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate	3.23%
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.67%
Available-for-sale Securities, Debt Maturities, Weighted Average Rate	1.99%
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount
Held-to-maturity	$ 2,511	5,254
Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity
Held-to-maturity, Fair Value	$ 2,361	$ 5,276

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