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Investment Securities (Details 2) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 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 | 54 | 63
Available-for-sale Securities, Less than 12 months, Fair Value | $ 43,323 | $ 47,809
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 684 | $ 897
Number of investments, 12 months or longer | Investment | 3 | 2
Available-for-sale Securities, 12 months or longer, Fair Value | $ 5,143 | $ 3,991
Available-for-sale Securities, 12 Months or longer, Unrealized losses | $ 46 | $ 30
Number of investments, Total | Investment | 57 | 65
Available-for-sale Securities, Fair Value, Total | $ 48,466 | $ 51,800
Available-for-sale Securities, Unrealized losses, Total | $ 730 | $ 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 | 4 | 5
Available-for-sale Securities, Less than 12 months, Fair Value | $ 3,967 | $ 5,144
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 90 | $ 113
Number of investments, 12 months or longer | Investment |  |
Available-for-sale Securities, 12 months or longer, Fair Value |  |
Available-for-sale Securities, 12 Months or longer, Unrealized losses |  |
Number of investments, Total | Investment | 4 | 5
Available-for-sale Securities, Fair Value, Total | $ 3,967 | $ 5,144
Available-for-sale Securities, Unrealized losses, Total | $ 90 | $ 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
Available-for-sale Securities, Less than 12 months, Fair Value |  | $ 1,437
Available-for-sale Securities, Less than 12 months, Unrealized losses |  | $ 16
Number of investments, 12 months or longer | Investment | 1 |
Available-for-sale Securities, 12 months or longer, Fair Value | $ 1,421 |
Available-for-sale Securities, 12 Months or longer, Unrealized losses | $ 16 |
Number of investments, Total | Investment | 1 | 1
Available-for-sale Securities, Fair Value, Total | $ 1,421 | $ 1,437
Available-for-sale Securities, Unrealized losses, Total | $ 16 | $ 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 | 24 | 32
Available-for-sale Securities, Less than 12 months, Fair Value | $ 10,519 | $ 13,936
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 198 | $ 292
Number of investments, 12 months or longer | Investment |  |
Available-for-sale Securities, 12 months or longer, Fair Value |  |
Available-for-sale Securities, 12 Months or longer, Unrealized losses |  |
Number of investments, Total | Investment | 24 | 32
Available-for-sale Securities, Fair Value, Total | $ 10,519 | $ 13,936
Available-for-sale Securities, Unrealized losses, Total | $ 198 | $ 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 | 26 | 25
Available-for-sale Securities, Less than 12 months, Fair Value | $ 28,837 | $ 27,292
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 396 | $ 476
Number of investments, 12 months or longer | Investment | 2 | 2
Available-for-sale Securities, 12 months or longer, Fair Value | $ 3,722 | $ 3,991
Available-for-sale Securities, 12 Months or longer, Unrealized losses | $ 30 | $ 30
Number of investments, Total | Investment | 28 | 27
Available-for-sale Securities, Fair Value, Total | $ 32,559 | $ 31,283
Available-for-sale Securities, Unrealized losses, Total | $ 426 | $ 506

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