Investment Securities Investment Securities-Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Mar. 31, 2018
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	$ 7,471
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	19,145
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	10,254
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	31,301
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis	68,171
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	7,457
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	18,742
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	9,707
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	29,922
Available-for-sale	$ 65,828	$ 60,709
Available-for-sale, Securities, Debt Maturities, within One Year, Weighted Average Rate	2.11%
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Weighted Average Rate	2.01%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate	2.08%
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.14%
Available-for-sale Securities, Debt Maturities, Weighted Average Rate	2.09%
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	$ 4,640
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	4,162
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Amortized Cost	3,042
Held-to-maturity	11,844	12,075
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	4,498
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	4,102
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	3,003
Held-to-maturity, Fair Value	$ 11,603	$ 11,909
Debt Securities, Held-to-maturity, Maturity, after One Through Five Years, Weighted Average Yield	2.41%
Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate	3.39%
Held-to-maturity Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.74%
Held-to-maturity Securities, Debt Maturities, Weighted Average Rate	2.84%

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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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