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Investment Securities Investment Securities Amortized Cost and Estimated Fair Value (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2016 | Mar. 31, 2015 | Mar. 31, 2016
Schedule of Held-to-maturity Securities [Line Items] |  |  |  |  |  |
Held-to-maturity, Amortized Cost | [1] | $ 14,458 |  |  | $ 15,311 |
Held-to-maturity, Gross Unrealized Gains | [1] | 432 |  |  | 342 |
Held-to-maturity, Gross Unrealized Losses | [1] | 0 |  |  | 0 |
Held-to-maturity, Fair Value | [1] | 14,890 |  |  | 15,653 |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |
Available-for-sale, Amortized Cost |  | 54,016 |  |  | 56,486 |
Available-for-sale, Gross Unrealized Gains |  | 63 |  |  | 72 |
Available-for-sale, Gross Unrealized Losses |  | 329 |  |  | 378 |
Available-for-sale, Fair Value |  | 53,750 |  |  | 56,180 |
securities amortized cost |  | 68,474 |  |  | 71,797 |
Unrealized Gain on Securities |  | 495 |  | $ 414 |  |
Unrealized Loss on Securities |  | 329 |  | $ 378 |  |
Investments, Fair Value Disclosure |  | 68,640 |  |  | 71,833 |
Government National Mortgage Association |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |
Available-for-sale, Amortized Cost |  | 3,344 |  |  | 4,578 |
Available-for-sale, Gross Unrealized Gains |  | 0 |  |  | 45 |
Available-for-sale, Gross Unrealized Losses |  | 15 |  |  | 0 |
Available-for-sale, Fair Value |  | 3,329 |  |  | 4,623 |
Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member] |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |
Available-for-sale, Amortized Cost |  | 6,782 |  |  | 7,778 |
Available-for-sale, Gross Unrealized Gains |  | 13 |  |  | 0 |
Available-for-sale, Gross Unrealized Losses |  | 43 |  |  | 100 |
Available-for-sale, Fair Value |  | 6,752 |  |  | 7,678 |
Federal National Mortgage Association |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |
Available-for-sale, Amortized Cost |  | 22,520 |  |  | 7,860 |
Available-for-sale, Gross Unrealized Gains |  | 28 |  |  | 0 |
Available-for-sale, Gross Unrealized Losses |  | 56 |  |  | 36 |
Available-for-sale, Fair Value |  | 22,492 |  |  | 7,824 |
Mortgage Backed Securities, Other [Member] |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |
Available-for-sale, Amortized Cost |  | 45 |  |  | 45 |
Available-for-sale, Gross Unrealized Gains |  | 0 |  |  | 0 |
Available-for-sale, Gross Unrealized Losses |  | 0 |  |  | 0 |
Available-for-sale, Fair Value |  | 45 |  |  | 45 |
Mortgage-backed securities |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |
Available-for-sale, Amortized Cost |  | 32,691 |  |  | 20,261 |
Available-for-sale, Gross Unrealized Gains |  | 41 |  |  | 45 |
Available-for-sale, Gross Unrealized Losses |  | 114 |  |  | 136 |
Available-for-sale, Fair Value |  | 32,618 |  |  | 20,170 |
US Government Agency Securities |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |
Available-for-sale, Amortized Cost |  | 5,849 |  |  | 26,077 |
Available-for-sale, Gross Unrealized Gains |  | 22 |  |  | 27 |
Available-for-sale, Gross Unrealized Losses |  | 0 |  |  | 35 |
Available-for-sale, Fair Value |  | 5,871 |  |  | 26,069 |
Corporate Bond Securities [Member] |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |
Available-for-sale, Amortized Cost |  | 5,116 |  |  |  |
Available-for-sale, Gross Unrealized Gains |  | 0 |  |  |  |
Available-for-sale, Gross Unrealized Losses |  | 25 |  |  |  |
Available-for-sale, Fair Value |  | 5,091 |  |  |  |
Other |  |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |  |
Available-for-sale, Amortized Cost |  | 10,360 |  |  | 10,148 |
Available-for-sale, Gross Unrealized Gains |  | 0 |  |  | 0 |
Available-for-sale, Gross Unrealized Losses |  | 190 |  |  | 207 |
Available-for-sale, Fair Value |  | 10,170 |  |  | 9,941 |
Government National Mortgage Association |  |  |  |  |  |
Schedule of Held-to-maturity Securities [Line Items] |  |  |  |  |  |
Held-to-maturity, Amortized Cost | [1] | 2,068 |  |  | 2,379 |
Held-to-maturity, Gross Unrealized Gains | [1] | 153 |  |  | 150 |
Held-to-maturity, Gross Unrealized Losses | [1] | 0 |  |  | 0 |
Held-to-maturity, Fair Value | [2] | 2,221 |  |  | 2,529 |
Federal National Mortgage Association |  |  |  |  |  |
Schedule of Held-to-maturity Securities [Line Items] |  |  |  |  |  |
Held-to-maturity, Amortized Cost | [1] | 11,390 |  |  | 11,932 |
Held-to-maturity, Gross Unrealized Gains | [1] | 254 |  |  | 192 |
Held-to-maturity, Gross Unrealized Losses | [1] | 0 |  |  | 0 |
Held-to-maturity, Fair Value | [2] | 11,644 |  |  | 12,124 |
Mortgage-backed securities |  |  |  |  |  |
Schedule of Held-to-maturity Securities [Line Items] |  |  |  |  |  |
Held-to-maturity, Amortized Cost | [1] | 13,458 |  |  | 14,311 |
Held-to-maturity, Gross Unrealized Gains | [1] | 407 |  |  | 342 |
Held-to-maturity, Gross Unrealized Losses | [1] | 0 |  |  | 0 |
Held-to-maturity, Fair Value | [1] | 13,865 |  |  | 14,653 |
Corporate Bond Securities [Member] |  |  |  |  |  |
Schedule of Held-to-maturity Securities [Line Items] |  |  |  |  |  |
Held-to-maturity, Amortized Cost |  | 1,000 | [1] |  | 1,000 |
Held-to-maturity, Gross Unrealized Gains | [1] | 25 |  |  | 0 |
Held-to-maturity, Gross Unrealized Losses |  | 0 | [1] |  | 0 | [2]
Held-to-maturity, Fair Value | [2] | $ 1,025 |  |  | $ 1,000 |
[1] | * The carrying amount and amortized cost are the same for all held-to-maturity securities, as no OTTI has been recorded.
[2] | * 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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