Investment Securities Text Figures (Details) (USD $)	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Schedule of Investments [Line Items]
Available-for-sale Securities, Change in Net Unrealized Holding Gain (Loss) before Taxes	$ 1,000,000	$ 400,000
Number of securities with unrealized loss	13	14
AFS Fair Value	116,100,000
Held-to-maturity Securities	9,043,000	11,081,000
Financial Instruments, Owned and Pledged as Collateral, at Fair Value	23,000,000
Pledged Assets, Not Separately Reported, Other	100,000
Available-for-sale Securities [Member]
Schedule of Investments [Line Items]
Percentage Available-for-sale Securities	92.80%
US Treasury Securities [Member]
Schedule of Investments [Line Items]
Percentage Available-for-Sale, Continuos Unrealized Loss Position	55.50%
Held-to-maturity securities
Schedule of Investments [Line Items]
Percentage Held-to-maturity Securities	7.20%
Held-to-maturity Securities	9,000,000
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Schedule of Investments [Line Items]
Held-to-maturity Securities	$ 9,043,000	$ 11,081,000

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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