Investment Securities Investment Securities-Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Sep. 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	$ 1,001
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	7,962
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	15,392
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	50,650
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis	75,005
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	7,925
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	15,377
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	50,807
Available-for-sale	$ 75,109	$ 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	2.63%
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.61%
Available-for-sale Securities, Debt Maturities, Weighted Average Rate	2.51%
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	$ 4,498
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	4,144
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Amortized Cost	2,038
Held-to-maturity	10,680	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	4,569
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	4,226
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	2,084
Held-to-maturity, Fair Value	$ 10,879	$ 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	3.35%
Held-to-maturity Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.86%
Held-to-maturity Securities, Debt Maturities, Weighted Average Rate	2.86%

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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Fair value 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 sixth through tenth 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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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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