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Investment Securities Investment Securities Unrealized losses and fair value of securities (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2015 | Mar. 31, 2015
Schedule of Held-to-maturity Securities [Line Items] |  |  |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | $ 159 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 12,879 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | 0 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 0 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss |  | 159 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value |  | 12,879 |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | 122 | $ 57
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 14,794 | 12,943
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | 1,288 | 1,090
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 52,367 | 58,499
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss |  | 1,410 | 1,147
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value |  | 67,161 | 71,442
Securities Continuous Loss Position Less than 12 months |  | 281 |
Securities Continuous Unrealized Loss Position Less than 12 months Fair Value |  | 27,673 |
Securities, Continuous Unrealized Loss Position ,12 months or Longer |  | 1,288 |
Securities, Continuous Unrealized Loss Position, 12 months or Longer, Fair Value |  | 52,367 |
Unrealized Loss on Securities |  | 1,569 | 1,147
Securities, Continuous Unrealized Loss Position, fair value |  | 80,040 |
Mortgage-backed securities |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | 29 | 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 3,887 | 0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | 397 | 287
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 16,873 | 22,297
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss |  | 426 | 287
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value |  | 20,760 | 22,297
US Government Agency Securities |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | 93 | 57
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 10,907 | 12,943
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | 548 | 605
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 25,837 | 26,400
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss |  | 641 | 662
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value |  | 36,744 | 39,343
Other |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | [1] | 0 | 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | [1] | 0 | 0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | [1] | 343 | 198
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | [1] | 9,657 | 9,802
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | [1] | 343 | 198
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | [1] | 9,657 | $ 9,802
Mortgage-backed securities |  |  |
Schedule of Held-to-maturity Securities [Line Items] |  |  |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | 149 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 11,889 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | 0 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 0 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss |  | 149 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value |  | 11,889 |
Corporate Bond Securities [Member] |  |  |
Schedule of Held-to-maturity Securities [Line Items] |  |  |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | 10 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 990 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | 0 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 0 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss |  | 10 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value |  | $ 990 |
[1] | (1) CRA fund comprised of over 95% agency securities.

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