Investment Securities-Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Mar. 31, 2019
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	$ 3,006
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	4,952
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	14,454
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	48,052
Debt Securities, Available-for-sale, Amortized Cost	70,464
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	3,004
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	4,908
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	14,438
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	48,093
Available-for-sale	$ 70,443	$ 79,845
Available-for-sale, Securities, Debt Maturities, within One Year, Weighted Average Rate	1.61%
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Weighted Average Rate	1.78%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate	2.40%
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.34%
Available-for-sale Securities, Debt Maturities, Weighted Average Rate	2.29%
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	$ 4,469
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	4,003
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Amortized Cost	1,975
Held-to-maturity	10,447	11,137
Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	4,515
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	4,067
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	2,022
Held-to-maturity, Fair Value	$ 10,604	$ 11,107
Debt Securities, Held-to-maturity, Maturity, after One Through Five Years, Weighted Average Yield	2.39%
Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate	3.33%
Held-to-maturity Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.86%
Held-to-maturity Securities, Debt Maturities, Weighted Average Rate	2.84%

Available-for-sale Securities, Debt Maturities, Weighted Average Rate

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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