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Investment Securities (Details 2) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2017 USD ($) Investment | Dec. 31, 2016 USD ($) Investment
Summary of gross unrealized losses on investment securities and fair market value of related securities |  |
Number of investments, Less than 12 months | Investment | 40 | 63
Available-for-sale Securities, Less than 12 months, Fair Value | $ 41,231 | $ 47,809
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 294 | $ 897
Number of investments, 12 months or longer | Investment | 16 | 2
Available-for-sale Securities, 12 months or longer, Fair Value | $ 14,891 | $ 3,991
Available-for-sale Securities, 12 Months or longer, Unrealized losses | $ 204 | $ 30
Number of investments, Total | Investment | 56 | 65
Available-for-sale Securities, Fair Value, Total | $ 56,122 | $ 51,800
Available-for-sale Securities, Unrealized losses, Total | $ 498 | $ 927
US government agencies [Member] |  |
Summary of gross unrealized losses on investment securities and fair market value of related securities |  |
Number of investments, Less than 12 months | Investment | 6 | 5
Available-for-sale Securities, Less than 12 months, Fair Value | $ 5,250 | $ 5,144
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 40 | $ 113
Number of investments, 12 months or longer | Investment | 1 |
Available-for-sale Securities, 12 months or longer, Fair Value | $ 740 |
Available-for-sale Securities, 12 Months or longer, Unrealized losses | $ 18 |
Number of investments, Total | Investment | 7 | 5
Available-for-sale Securities, Fair Value, Total | $ 5,990 | $ 5,144
Available-for-sale Securities, Unrealized losses, Total | $ 58 | $ 113
SBA securities [Member] |  |
Summary of gross unrealized losses on investment securities and fair market value of related securities |  |
Number of investments, Less than 12 months | Investment | 1 | 1
Available-for-sale Securities, Less than 12 months, Fair Value | $ 2,937 | $ 1,437
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 12 | $ 16
Number of investments, 12 months or longer | Investment | 1 |
Available-for-sale Securities, 12 months or longer, Fair Value | $ 1,402 |
Available-for-sale Securities, 12 Months or longer, Unrealized losses | $ 6 |
Number of investments, Total | Investment | 2 | 1
Available-for-sale Securities, Fair Value, Total | $ 4,339 | $ 1,437
Available-for-sale Securities, Unrealized losses, Total | $ 18 | $ 16
State and political subdivisions [Member] |  |
Summary of gross unrealized losses on investment securities and fair market value of related securities |  |
Number of investments, Less than 12 months | Investment | 8 | 32
Available-for-sale Securities, Less than 12 months, Fair Value | $ 3,652 | $ 13,936
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 12 | $ 292
Number of investments, 12 months or longer | Investment | 6 |
Available-for-sale Securities, 12 months or longer, Fair Value | $ 2,910 |
Available-for-sale Securities, 12 Months or longer, Unrealized losses | $ 48 |
Number of investments, Total | Investment | 14 | 32
Available-for-sale Securities, Fair Value, Total | $ 6,562 | $ 13,936
Available-for-sale Securities, Unrealized losses, Total | $ 60 | $ 292
Mortgage-backed securities [Member] |  |
Summary of gross unrealized losses on investment securities and fair market value of related securities |  |
Number of investments, Less than 12 months | Investment | 25 | 25
Available-for-sale Securities, Less than 12 months, Fair Value | $ 29,392 | $ 27,292
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 230 | $ 476
Number of investments, 12 months or longer | Investment | 8 | 2
Available-for-sale Securities, 12 months or longer, Fair Value | $ 9,839 | $ 3,991
Available-for-sale Securities, 12 Months or longer, Unrealized losses | $ 132 | $ 30
Number of investments, Total | Investment | 33 | 27
Available-for-sale Securities, Fair Value, Total | $ 39,231 | $ 31,283
Available-for-sale Securities, Unrealized losses, Total | $ 362 | $ 506

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