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Investment Securities Text Figures (Details) | 6 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2015 USD ($) | Mar. 31, 2015 USD ($)
Schedule of Investments [Line Items] |  |  |
Number of agencies with unrealized loss more than 12 months |  | 7 |
Available-for-sale |  | $ 75,760,000 | $ 101,185,000
Percentage Available-for-sale Securities |  | 82.50% |
Held-to-maturity |  | $ 16,087,000 | 11,922,000
Held-to-maturity Securities, Amortized Cost | [1] | $ 16,087,000 | $ 11,922,000
Percentage Held-to-maturity Securities |  | 17.50% |
Trading Securities |  | $ 0 |
Number of securities with unrealized loss |  | 21 | 23
US Government Agency Securities |  |  |
Schedule of Investments [Line Items] |  |  |
Percentage Available-for-Sale, Continuos Unrealized Loss Position |  | 53.00% |
Available-for-sale |  | $ 43,140,000 | $ 57,850,000
Mortgage-backed securities |  |  |
Schedule of Investments [Line Items] |  |  |
Percentage Available-for-Sale, Continuos Unrealized Loss Position |  | 30.40% |
Number of MBS with unrealized loss more than 12 months |  | 10 |
Available-for-sale |  | $ 21,871,000 | 27,019,000
Held-to-maturity Securities, Amortized Cost | [1] | $ 15,087,000 | $ 11,922,000
[1] | * The carrying amount and amortized cost are the same for all held-to-maturity securities, as no OTTI has been recorded.

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