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Investment Securities Text Figures (Details) (USD $)	6 Months Ended	12 Months Ended
	Sep. 30, 2013	Mar. 31, 2013
Schedule of Investments [Line Items]
AFS Fair Value	$ 87,200,000
Percentage Available-for-sale Securities	0.00%
Held to maturity amortized cost	12,400,000
Held-to-maturity Securities	$ 104,511,000	$ 124,052,000
Percentage Held-to-maturity Securities	12.50%
Number of securities with unrealized loss	32	13
Number of MBS with unrealized loss more than 12 months	1
US Government Agencies Debt Securities [Member]
Schedule of Investments [Line Items]
Percentage Available-for-Sale, Continuos Unrealized Loss Position	52.70%
percentage of securities in a loss position for more than 12 months	2.20%
Collateralized Mortgage Backed Securities [Member]
Schedule of Investments [Line Items]
Percentage Available-for-Sale, Continuos Unrealized Loss Position	33.90%

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