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Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands | Sep. 30, 2015 | Dec. 31, 2014
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Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | $ 86,471 | $ 116,437
Held to maturity, Fair Value | 88,104 | 118,643
Held-to-maturity, Gross Unrealized Gains | 1,648 | 2,271
Held-to-maturity, Gross Unrealized Losses | (15) | (65)
Available-for-sale, Amortized Cost | 331,024 | 199,045
Available-for-sale, Fair Value | 333,856 | 200,848
Available-for-sale, Gross Unrealized Gains | 3,018 | 2,234
Available-for-sale, Gross Unrealized Losses | (186) | (431)
Total investment securities, Amortized Cost | 417,495 | 315,482
Total investment securities, Fair Value | 421,960 | 319,491
Total investment securities, Gross Unrealized Gains | 4,666 | 4,505
Total investment securities, Gross Unrealized Losses | (201) | (496)
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 | 116,513 | 92,963
Available-for-sale, Fair Value | 117,963 | 94,214
Available-for-sale, Gross Unrealized Gains | 1,488 | 1,262
Available-for-sale, Gross Unrealized Losses | (38) | (11)
CMOs issued by FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 16,211 | 14,771
Available-for-sale, Fair Value | 16,385 | 14,790
Available-for-sale, Gross Unrealized Gains | 208 | 77
Available-for-sale, Gross Unrealized Losses | (34) | (58)
CMOs issued by FHLMC |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 24,645 | 31,238
Available-for-sale, Fair Value | 24,869 | 31,260
Available-for-sale, Gross Unrealized Gains | 239 | 109
Available-for-sale, Gross Unrealized Losses | (15) | (87)
CMOs issued by GNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 11,951 | 17,573
Available-for-sale, Fair Value | 12,200 | 17,855
Available-for-sale, Gross Unrealized Gains | 254 | 298
Available-for-sale, Gross Unrealized Losses | (5) | (16)
Debentures of government sponsored agencies |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 101,987 | 14,694
Available-for-sale, Fair Value | 102,165 | 14,557
Available-for-sale, Gross Unrealized Gains | 229 | 95
Available-for-sale, Gross Unrealized Losses | (51) | (232)
Privately-issued CMOs |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 4,700 | 7,137
Available-for-sale, Fair Value | 4,891 | 7,294
Available-for-sale, Gross Unrealized Gains | 193 | 172
Available-for-sale, Gross Unrealized Losses | (2) | (15)
Obligations of state and political subdivisions |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 50,073 | 15,733
Available-for-sale, Fair Value | 50,377 | 15,880
Available-for-sale, Gross Unrealized Gains | 345 | 155
Available-for-sale, Gross Unrealized Losses | (41) | (8)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 4,944 | 4,936
Available-for-sale, Fair Value | 5,006 | 4,998
Available-for-sale, Gross Unrealized Gains | 62 | 66
Available-for-sale, Gross Unrealized Losses | 0 | (4)
Obligations of state and political subdivisions |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | 50,570 | 63,425
Held to maturity, Fair Value | 51,867 | 65,121
Held-to-maturity, Gross Unrealized Gains | 1,302 | 1,736
Held-to-maturity, Gross Unrealized Losses | (5) | (40)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | 23,578 | 40,257
Held to maturity, Fair Value | 23,662 | 40,448
Held-to-maturity, Gross Unrealized Gains | 87 | 216
Held-to-maturity, Gross Unrealized Losses | (3) | (25)
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 | 12,323 | 12,755
Held to maturity, Fair Value | 12,575 | 13,074
Held-to-maturity, Gross Unrealized Gains | 259 | 319
Held-to-maturity, Gross Unrealized Losses | $ (7) | $ 0

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