Investment Securities Investment Securities Carrying Value (Amortized Cost) and Fair Value by remaining period of contractual maturity (Details) - USD ($) $ in Thousands		Sep. 30, 2016	Mar. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Amortized Cost Basis		$ 10,608
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value		$ 10,595
Available-for-sale Securities, Debt Maturities, after One Through Five Years, Weighted Average Rate		1.71%
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Amortized Cost Basis		$ 12,655
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value		$ 12,651
Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate		1.91%
Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis		$ 30,753
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value		$ 30,504
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate		1.12%
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis		$ 54,016
Available-for-sale		$ 53,750	$ 56,180
Available-for-sale Securities, Debt Maturities, Weighted Average Rate		1.43%
Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Net Carrying Amount		$ 6,705
Held-to-maturity Securities, Debt Maturities, Year Six Through Ten, Fair Value		$ 6,934
Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Weighted Average Rate		3.00%
Held-to-maturity Securities, Debt Maturities, after Ten Years, Net Carrying Amount		$ 7,753
Held-to-maturity Securities, Debt Maturities, after Ten Years, Fair Value		$ 7,956
Held-to-maturity Securities, Debt Maturities, after Ten Years, Weighted Average Rate		2.39%
Held-to-maturity, Amortized Cost	[1]	$ 14,458	15,311
Held-to-maturity Securities, Fair Value	[1]	$ 14,890	$ 15,653
Held-to-maturity Securities, Debt Maturities, Weighted Average Rate		2.67%

[1] * The carrying amount and amortized cost are the same for all held-to-maturity securities, as no OTTI has been recorded.