Investment Securities Carrying Value (Amortized Cost) and Fair Value by remaining period of contractual maturity (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Mar. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
AFS Amortized Cost One through five years	$ 2,000
AFS Amortized Cost Five through ten years	24,387
AFS Amortized Cost After ten years	64,651
AFS Amortized Cost Total	91,038
AFS Fair Value One through five years	1,967
AFS Fair Value Five through ten years	22,823
AFS Fair Value After ten years	59,812
Available-for-sale, at fair value	84,602	116,051
AFS Weighted Average Rate One through five years	1.50%
AFS Weighted Average Rate Five through ten years	1.65%
Available-for-sale Securities, Debt Maturities, after Ten Years, Weighted Average Rate	1.70%
AFS Weighted Average Rate Total	1.69%
Held-to-Maturity Security Amortized Cost One through Five years	113
HTM Amortized Cost Five through ten years	5,209
HTM Amortized Cost After ten years	6,767
HTM Amortized Cost Total	12,089
Held-to-maturity securities, one through five years, fair value	115
HTM Fair Value Five through ten years	4,860
HTM Fair Value After ten years	7,117
HTM Fair Value Total	$ 12,092
Held-to-maturity Securities, Debt Maturities, One Through Five Years, Weighted Average Rate	2.68%
HTM Weighted Average Rate Five through ten years	2.49%
HTM Weighted Average Rate After ten years	3.63%
HTM Weighted Average Rate Total	3.13%