Investment Securities Investment Securities-Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Jun. 30, 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	$ 1,003
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	8,275
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	16,850
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	52,339
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis	78,467
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	1,000
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	8,235
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	16,813
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	52,343
Available-for-sale	$ 78,391	$ 79,845
Available-for-sale, Securities, Debt Maturities, within One Year, Weighted Average Rate	1.65%
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Weighted Average Rate	1.72%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate	2.81%
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.67%
Available-for-sale Securities, Debt Maturities, Weighted Average Rate	2.59%
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	$ 4,527
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	4,252
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Amortized Cost	2,113
Held-to-maturity	10,892	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	4,568
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	4,312
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	2,147
Held-to-maturity, Fair Value	$ 11,027	$ 11,107
Debt Securities, Held-to-maturity, Maturity, after One Through Five Years, Weighted Average Yield	2.40%
Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate	3.32%
Held-to-maturity Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.79%
Held-to-maturity Securities, Debt Maturities, Weighted Average Rate	2.83%

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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