Investment Securities Investment Securities-Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Sep. 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	$ 7,479
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	18,643
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	7,937
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	60,827
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis	94,886
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	7,464
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	18,200
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	7,457
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	59,074
Available-for-sale	$ 92,195	$ 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	2.03%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate	2.19%
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.69%
Available-for-sale Securities, Debt Maturities, Weighted Average Rate	2.47%
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	$ 4,613
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	4,090
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Amortized Cost	2,842
Held-to-maturity	11,545	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	4,444
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	3,998
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	2,784
Held-to-maturity, Fair Value	$ 11,226	$ 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	3.44%
Held-to-maturity Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.45%
Held-to-maturity Securities, Debt Maturities, Weighted Average Rate	2.78%

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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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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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