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Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands | Jun. 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 | $ 94,475 | $ 116,437
Held to maturity, Fair Value | 96,017 | 118,643
Held-to-maturity, Gross Unrealized Gains | 1,614 | 2,271
Held-to-maturity, Gross Unrealized Losses | (72) | (65)
Available-for-sale, Amortized Cost | 252,709 | 199,045
Available-for-sale, Fair Value | 254,018 | 200,848
Available-for-sale, Gross Unrealized Gains | 1,830 | 2,234
Available-for-sale, Gross Unrealized Losses | (521) | (431)
Total investment securities, Amortized Cost | 347,184 | 315,482
Total investment securities, Fair Value | 350,035 | 319,491
Total investment securities, Gross Unrealized Gains | 3,444 | 4,505
Total investment securities, Gross Unrealized Losses | (593) | (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 | 120,719 | 92,963
Available-for-sale, Fair Value | 121,273 | 94,214
Available-for-sale, Gross Unrealized Gains | 748 | 1,262
Available-for-sale, Gross Unrealized Losses | (194) | (11)
CMOs issued by FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 12,993 | 14,771
Available-for-sale, Fair Value | 13,106 | 14,790
Available-for-sale, Gross Unrealized Gains | 150 | 77
Available-for-sale, Gross Unrealized Losses | (37) | (58)
CMOs issued by FHLMC |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 27,065 | 31,238
Available-for-sale, Fair Value | 27,191 | 31,260
Available-for-sale, Gross Unrealized Gains | 164 | 109
Available-for-sale, Gross Unrealized Losses | (38) | (87)
CMOs issued by GNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 13,950 | 17,573
Available-for-sale, Fair Value | 14,216 | 17,855
Available-for-sale, Gross Unrealized Gains | 274 | 298
Available-for-sale, Gross Unrealized Losses | (8) | (16)
Debentures of government sponsored agencies |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 31,121 | 14,694
Available-for-sale, Fair Value | 31,072 | 14,557
Available-for-sale, Gross Unrealized Gains | 98 | 95
Available-for-sale, Gross Unrealized Losses | (147) | (232)
Privately-issued CMOs |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 5,011 | 7,137
Available-for-sale, Fair Value | 5,209 | 7,294
Available-for-sale, Gross Unrealized Gains | 200 | 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 | 36,909 | 15,733
Available-for-sale, Fair Value | 36,937 | 15,880
Available-for-sale, Gross Unrealized Gains | 123 | 155
Available-for-sale, Gross Unrealized Losses | (95) | (8)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 4,941 | 4,936
Available-for-sale, Fair Value | 5,014 | 4,998
Available-for-sale, Gross Unrealized Gains | 73 | 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 | 54,183 | 63,425
Held to maturity, Fair Value | 55,455 | 65,121
Held-to-maturity, Gross Unrealized Gains | 1,332 | 1,736
Held-to-maturity, Gross Unrealized Losses | (60) | (40)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | 27,615 | 40,257
Held to maturity, Fair Value | 27,732 | 40,448
Held-to-maturity, Gross Unrealized Gains | 122 | 216
Held-to-maturity, Gross Unrealized Losses | (5) | (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 | 12,677 | 12,755
Held to maturity, Fair Value | 12,830 | 13,074
Held-to-maturity, Gross Unrealized Gains | 160 | 319
Held-to-maturity, Gross Unrealized Losses | $ (7) | $ 0

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