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Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands | Mar. 31, 2017 | Dec. 31, 2016
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Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | $ 172,272 | $ 44,438
Held to maturity, Fair Value | 172,421 | 45,097
Held-to-maturity, Gross Unrealized Gains | 828 | 820
Held-to-maturity, Gross Unrealized Losses | (679) | (161)
Available-for-sale, Amortized Cost | 242,650 | 378,254
Available-for-sale, Fair Value | 241,684 | 372,580
Available-for-sale, Gross Unrealized Gains | 831 | 575
Available-for-sale, Gross Unrealized Losses | (1,797) | (6,249)
Total investment securities, Amortized Cost | 414,922 | 422,692
Total investment securities, Fair Value | 414,105 | 417,677
Total investment securities, Gross Unrealized Gains | 1,659 | 1,395
Total investment securities, Gross Unrealized Losses | (2,476) | (6,410)
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 | 93,676 | 193,998
Available-for-sale, Fair Value | 93,719 | 190,566
Available-for-sale, Gross Unrealized Gains | 328 | 145
Available-for-sale, Gross Unrealized Losses | (285) | (3,577)
CMOs issued by FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 12,897 | 13,790
Available-for-sale, Fair Value | 12,874 | 13,772
Available-for-sale, Gross Unrealized Gains | 84 | 91
Available-for-sale, Gross Unrealized Losses | (107) | (109)
CMOs issued by FHLMC |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 10,237 | 43,452
Available-for-sale, Fair Value | 10,260 | 42,758
Available-for-sale, Gross Unrealized Gains | 25 | 37
Available-for-sale, Gross Unrealized Losses | (2) | (731)
CMOs issued by GNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 6,181 | 6,844
Available-for-sale, Fair Value | 6,268 | 6,945
Available-for-sale, Gross Unrealized Gains | 87 | 102
Available-for-sale, Gross Unrealized Losses | 0 | (1)
Debentures of government sponsored agencies |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 35,488 | 35,486
Available-for-sale, Fair Value | 35,386 | 35,403
Available-for-sale, Gross Unrealized Gains | 2 | 7
Available-for-sale, Gross Unrealized Losses | (104) | (90)
Privately issued CMOs |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 305 | 419
Available-for-sale, Fair Value | 305 | 419
Available-for-sale, Gross Unrealized Gains | 0 | 1
Available-for-sale, Gross Unrealized Losses | 0 | (1)
Obligations of state and political subdivisions |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 78,905 | 79,306
Available-for-sale, Fair Value | 77,843 | 77,701
Available-for-sale, Gross Unrealized Gains | 237 | 135
Available-for-sale, Gross Unrealized Losses | (1,299) | (1,740)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, Amortized Cost | 4,961 | 4,959
Available-for-sale, Fair Value | 5,029 | 5,016
Available-for-sale, Gross Unrealized Gains | 68 | 57
Available-for-sale, Gross Unrealized Losses | 0 | 0
Obligations of state and political subdivisions |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | 27,741 | 30,856
Held to maturity, Fair Value | 28,407 | 31,544
Held-to-maturity, Gross Unrealized Gains | 669 | 694
Held-to-maturity, Gross Unrealized Losses | (3) | (6)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | 3,514 | 3,519
Held to maturity, Fair Value | 3,511 | 3,518
Held-to-maturity, Gross Unrealized Gains | 0 | 0
Held-to-maturity, Gross Unrealized Losses | (3) | (1)
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 | 109,357 | 10,063
Held to maturity, Fair Value | 108,843 | 10,035
Held-to-maturity, Gross Unrealized Gains | 109 | 126
Held-to-maturity, Gross Unrealized Losses | (623) | (154)
CMOs issued by FHLMC |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, Amortized Cost | 31,660 | 0
Held to maturity, Fair Value | 31,660 | 0
Held-to-maturity, Gross Unrealized Gains | 50 | 0
Held-to-maturity, Gross Unrealized Losses | $ (50) | $ 0

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