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Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands | Jun. 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 | $ 58,491 | $ 69,637
Held to maturity, Fair Value | 60,160 | 71,054
Held-to-maturity, Gross Unrealized Gains | 1,678 | 1,459
Held-to-maturity, Gross Unrealized Losses | (9) | (42)
Available-for-sale, Amortized Cost | 318,336 | 417,410
Available-for-sale, Fair Value | 323,361 | 417,787
Available-for-sale, Gross Unrealized Gains | 5,037 | 1,883
Available-for-sale, Gross Unrealized Losses | (12) | (1,506)
Total investment securities, Amortized Cost | 376,827 | 487,047
Total investment securities, Fair Value | 383,521 | 488,841
Total investment securities, Gross Unrealized Gains | 6,715 | 3,342
Total investment securities, Gross Unrealized Losses | (21) | (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 | 111,682 | 138,222
Available-for-sale, Fair Value | 113,877 | 138,462
Available-for-sale, Gross Unrealized Gains | 2,195 | 694
Available-for-sale, Gross Unrealized Losses | 0 | (454)
CMOs issued by FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 23,061 | 18,266
Available-for-sale, Fair Value | 23,387 | 18,219
Available-for-sale, Gross Unrealized Gains | 331 | 97
Available-for-sale, Gross Unrealized Losses | (5) | (144)
CMOs issued by FHLMC |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 21,110 | 22,889
Available-for-sale, Fair Value | 21,451 | 22,932
Available-for-sale, Gross Unrealized Gains | 341 | 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 | 8,470 | 10,326
Available-for-sale, Fair Value | 8,692 | 10,480
Available-for-sale, Gross Unrealized Gains | 222 | 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 | 83,566 | 161,690
Available-for-sale, Fair Value | 83,758 | 160,892
Available-for-sale, Gross Unrealized Gains | 193 | 28
Available-for-sale, Gross Unrealized Losses | (1) | (826)
Privately issued CMOs |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 768 | 3,960
Available-for-sale, Fair Value | 768 | 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 | 64,725 | 57,110
Available-for-sale, Fair Value | 66,452 | 57,673
Available-for-sale, Gross Unrealized Gains | 1,729 | 580
Available-for-sale, Gross Unrealized Losses | (2) | (17)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 4,954 | 4,947
Available-for-sale, Fair Value | 4,976 | 4,979
Available-for-sale, Gross Unrealized Gains | 25 | 43
Available-for-sale, Gross Unrealized Losses | (3) | (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 | 39,009 | 42,919
Held to maturity, Fair Value | 40,337 | 44,146
Held-to-maturity, Gross Unrealized Gains | 1,336 | 1,246
Held-to-maturity, Gross Unrealized Losses | (8) | (19)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | 8,529 | 15,072
Held to maturity, Fair Value | 8,534 | 15,098
Held-to-maturity, Gross Unrealized Gains | 6 | 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 | 10,953 | 11,646
Held to maturity, Fair Value | 11,289 | 11,810
Held-to-maturity, Gross Unrealized Gains | 336 | 171
Held-to-maturity, Gross Unrealized Losses | $ 0 | $ (7)

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