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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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