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Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands | Mar. 31, 2016 | Dec. 31, 2015
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Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | $ 63,246 | $ 69,637
Held to maturity, Fair Value | 64,848 | 71,054
Held-to-maturity, Gross Unrealized Gains | 1,624 | 1,459
Held-to-maturity, Gross Unrealized Losses | (22) | (42)
Available-for-sale, Amortized Cost | 333,044 | 417,410
Available-for-sale, Fair Value | 336,234 | 417,787
Available-for-sale, Gross Unrealized Gains | 3,397 | 1,883
Available-for-sale, Gross Unrealized Losses | (207) | (1,506)
Total investment securities, Amortized Cost | 396,290 | 487,047
Total investment securities, Fair Value | 401,082 | 488,841
Total investment securities, Gross Unrealized Gains | 5,021 | 3,342
Total investment securities, Gross Unrealized Losses | (229) | (1,548)
Mortgage-backed Securities, Issued by FHLMC and FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 128,434 | 138,222
Available-for-sale, Fair Value | 129,983 | 138,462
Available-for-sale, Gross Unrealized Gains | 1,613 | 694
Available-for-sale, Gross Unrealized Losses | (64) | (454)
CMOs issued by FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 17,190 | 18,266
Available-for-sale, Fair Value | 17,290 | 18,219
Available-for-sale, Gross Unrealized Gains | 147 | 97
Available-for-sale, Gross Unrealized Losses | (47) | (144)
CMOs issued by FHLMC |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 23,287 | 22,889
Available-for-sale, Fair Value | 23,471 | 22,932
Available-for-sale, Gross Unrealized Gains | 196 | 82
Available-for-sale, Gross Unrealized Losses | (12) | (39)
CMOs issued by GNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 9,394 | 10,326
Available-for-sale, Fair Value | 9,562 | 10,480
Available-for-sale, Gross Unrealized Gains | 172 | 169
Available-for-sale, Gross Unrealized Losses | (4) | (15)
Debentures of government sponsored agencies |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 87,592 | 161,690
Available-for-sale, Fair Value | 87,623 | 160,892
Available-for-sale, Gross Unrealized Gains | 93 | 28
Available-for-sale, Gross Unrealized Losses | (62) | (826)
Privately-issued CMOs |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 3,785 | 3,960
Available-for-sale, Fair Value | 3,971 | 4,150
Available-for-sale, Gross Unrealized Gains | 187 | 190
Available-for-sale, Gross Unrealized Losses | (1) | 0
Obligations of state and political subdivisions |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 58,412 | 57,110
Available-for-sale, Fair Value | 59,373 | 57,673
Available-for-sale, Gross Unrealized Gains | 964 | 580
Available-for-sale, Gross Unrealized Losses | (3) | (17)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 4,950 | 4,947
Available-for-sale, Fair Value | 4,961 | 4,979
Available-for-sale, Gross Unrealized Gains | 25 | 43
Available-for-sale, Gross Unrealized Losses | (14) | (11)
Obligations of state and political subdivisions |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | 40,254 | 42,919
Held to maturity, Fair Value | 41,580 | 44,146
Held-to-maturity, Gross Unrealized Gains | 1,338 | 1,246
Held-to-maturity, Gross Unrealized Losses | (12) | (19)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | 11,544 | 15,072
Held to maturity, Fair Value | 11,560 | 15,098
Held-to-maturity, Gross Unrealized Gains | 19 | 42
Held-to-maturity, Gross Unrealized Losses | (3) | (16)
MBS pass-through securities issued by FHLMC and FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | 11,448 | 11,646
Held to maturity, Fair Value | 11,708 | 11,810
Held-to-maturity, Gross Unrealized Gains | 267 | 171
Held-to-maturity, Gross Unrealized Losses | $ (7) | $ (7)

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