Investment Securities Investment Securities-Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands	Dec. 31, 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	$ 8,495
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	17,650
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	18,466
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	59,438
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis	104,049
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	8,472
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	17,364
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	18,077
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	58,417
Available-for-sale	$ 102,330	$ 60,709
Available-for-sale, Securities, Debt Maturities, within One Year, Weighted Average Rate	2.05%
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Weighted Average Rate	2.05%
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate	2.73%
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.84%
Available-for-sale Securities, Debt Maturities, Weighted Average Rate	2.63%
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	$ 4,585
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	4,025
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Amortized Cost	2,730
Held-to-maturity	11,340	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	4,508
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	3,992
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	2,694
Held-to-maturity, Fair Value	$ 11,194	$ 11,909
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	3.46%
Held-to-maturity Securities, Debt Maturities, after Ten Years, Weighted Average Rate	2.70%
Held-to-maturity Securities, Debt Maturities, Weighted Average Rate	2.85%

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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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