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Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands | Sep. 30, 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 | $ 46,423 | $ 69,637
Held to maturity, Fair Value | 47,867 | 71,054
Held-to-maturity, Gross Unrealized Gains | 1,448 | 1,459
Held-to-maturity, Gross Unrealized Losses | (4) | (42)
Available-for-sale, Amortized Cost | 374,802 | 417,410
Available-for-sale, Fair Value | 378,996 | 417,787
Available-for-sale, Gross Unrealized Gains | 4,523 | 1,883
Available-for-sale, Gross Unrealized Losses | (329) | (1,506)
Total investment securities, Amortized Cost | 421,225 | 487,047
Total investment securities, Fair Value | 426,863 | 488,841
Total investment securities, Gross Unrealized Gains | 5,971 | 3,342
Total investment securities, Gross Unrealized Losses | (333) | (1,548)
MBS pass-through securities issued by FHLMC and FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 196,987 | 138,222
Available-for-sale, Fair Value | 198,999 | 138,462
Available-for-sale, Gross Unrealized Gains | 2,239 | 694
Available-for-sale, Gross Unrealized Losses | (227) | (454)
CMOs issued by FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 14,885 | 18,266
Available-for-sale, Fair Value | 15,104 | 18,219
Available-for-sale, Gross Unrealized Gains | 219 | 97
Available-for-sale, Gross Unrealized Losses | 0 | (144)
CMOs issued by FHLMC |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 30,555 | 22,889
Available-for-sale, Fair Value | 30,887 | 22,932
Available-for-sale, Gross Unrealized Gains | 332 | 82
Available-for-sale, Gross Unrealized Losses | 0 | (39)
CMOs issued by GNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 7,654 | 10,326
Available-for-sale, Fair Value | 7,834 | 10,480
Available-for-sale, Gross Unrealized Gains | 180 | 169
Available-for-sale, Gross Unrealized Losses | 0 | (15)
Debentures of government sponsored agencies |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 40,486 | 161,690
Available-for-sale, Fair Value | 40,576 | 160,892
Available-for-sale, Gross Unrealized Gains | 98 | 28
Available-for-sale, Gross Unrealized Losses | (8) | (826)
Privately issued CMOs |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 560 | 3,960
Available-for-sale, Fair Value | 560 | 4,150
Available-for-sale, Gross Unrealized Gains | 1 | 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 | 78,719 | 57,110
Available-for-sale, Fair Value | 80,027 | 57,673
Available-for-sale, Gross Unrealized Gains | 1,401 | 580
Available-for-sale, Gross Unrealized Losses | (93) | (17)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 4,956 | 4,947
Available-for-sale, Fair Value | 5,009 | 4,979
Available-for-sale, Gross Unrealized Gains | 53 | 43
Available-for-sale, Gross Unrealized Losses | 0 | (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 | 32,765 | 42,919
Held to maturity, Fair Value | 33,868 | 44,146
Held-to-maturity, Gross Unrealized Gains | 1,106 | 1,246
Held-to-maturity, Gross Unrealized Losses | (3) | (19)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | 3,524 | 15,072
Held to maturity, Fair Value | 3,523 | 15,098
Held-to-maturity, Gross Unrealized Gains | 0 | 42
Held-to-maturity, Gross Unrealized Losses | (1) | (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 | 10,134 | 11,646
Held to maturity, Fair Value | 10,476 | 11,810
Held-to-maturity, Gross Unrealized Gains | 342 | 171
Held-to-maturity, Gross Unrealized Losses | $ 0 | $ (7)

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