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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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