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Investment Securities (Details 2) $ in Thousands | Dec. 31, 2018 USD ($) Investments | Dec. 31, 2017 USD ($) Investments
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Summary of gross unrealized losses on investment securities and fair market value of related securities |  |
Number of investments, Less than 12 months | Investments | 8 | 25
Available-for-sale Securities, Less than 12 months, Fair Value | $ 11,746 | $ 27,846
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 64 | $ 245
Number of investments, 12 months or longer | Investments | 53 | 28
Available-for-sale Securities, 12 months or longer, Fair Value | $ 46,524 | $ 27,511
Available-for-sale Securities, 12 months or Longer, Unrealized losses | $ 1,270 | $ 518
Number of investments, Total | Investments | 61 | 53
Available-for-sale Securities, Fair Value, Total | $ 58,270 | $ 55,357
Available-for-sale Securities, Unrealized Losses, Total | $ 1,334 | $ 763
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 | Investments | 1 | 5
Available-for-sale Securities, Less than 12 months, Fair Value | $ 1,246 | $ 4,184
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 3 | $ 22
Number of investments, 12 months or longer | Investments | 8 | 4
Available-for-sale Securities, 12 months or longer, Fair Value | $ 7,035 | $ 3,968
Available-for-sale Securities, 12 months or Longer, Unrealized losses | $ 191 | $ 75
Number of investments, Total | Investments | 9 | 9
Available-for-sale Securities, Fair Value, Total | $ 8,281 | $ 8,152
Available-for-sale Securities, Unrealized Losses, Total | $ 194 | $ 97
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 | Investments |  | 1
Available-for-sale Securities, Less than 12 months, Fair Value |  | $ 2,936
Available-for-sale Securities, Less than 12 months, Unrealized losses |  | $ 13
Number of investments, 12 months or longer | Investments | 2 | 1
Available-for-sale Securities, 12 months or longer, Fair Value | $ 3,525 | $ 1,127
Available-for-sale Securities, 12 months or Longer, Unrealized losses | $ 103 | $ 11
Number of investments, Total | Investments | 2 | 2
Available-for-sale Securities, Fair Value, Total | $ 3,525 | $ 4,063
Available-for-sale Securities, Unrealized Losses, Total | $ 103 | $ 24
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 | Investments |  | 3
Available-for-sale Securities, Less than 12 months, Fair Value |  | $ 1,214
Available-for-sale Securities, Less than 12 months, Unrealized losses |  | $ 9
Number of investments, 12 months or longer | Investments | 7 | 2
Available-for-sale Securities, 12 months or longer, Fair Value | $ 2,829 | $ 792
Available-for-sale Securities, 12 months or Longer, Unrealized losses | $ 63 | $ 16
Number of investments, Total | Investments | 7 | 5
Available-for-sale Securities, Fair Value, Total | $ 2,829 | $ 2,006
Available-for-sale Securities, Unrealized Losses, Total | $ 63 | $ 25
Asset-backed [Member] |  |
Summary of gross unrealized losses on investment securities and fair market value of related securities |  |
Number of investments, Less than 12 months | Investments | 4 |
Available-for-sale Securities, Less than 12 months, Fair Value | $ 6,707 |
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 49 |
Number of investments, 12 months or longer | Investments |  |
Available-for-sale Securities, 12 months or longer, Fair Value |  |
Available-for-sale Securities, 12 months or Longer, Unrealized losses |  |
Number of investments, Total | Investments | 4 |
Available-for-sale Securities, Fair Value, Total | $ 6,707 |
Available-for-sale Securities, Unrealized Losses, Total | $ 49 |
Mortgage-backed [Member] | FHLMC [Member] |  |
Summary of gross unrealized losses on investment securities and fair market value of related securities |  |
Number of investments, Less than 12 months | Investments |  | 3
Available-for-sale Securities, Less than 12 months, Fair Value |  | $ 2,897
Available-for-sale Securities, Less than 12 months, Unrealized losses |  | $ 26
Number of investments, 12 months or longer | Investments | 10 | 7
Available-for-sale Securities, 12 months or longer, Fair Value | $ 7,402 | $ 6,056
Available-for-sale Securities, 12 months or Longer, Unrealized losses | $ 242 | $ 123
Number of investments, Total | Investments | 10 | 10
Available-for-sale Securities, Fair Value, Total | $ 7,402 | $ 8,953
Available-for-sale Securities, Unrealized Losses, Total | $ 242 | $ 149
Mortgage-backed [Member] | FNMA [Member] |  |
Summary of gross unrealized losses on investment securities and fair market value of related securities |  |
Number of investments, Less than 12 months | Investments | 2 | 11
Available-for-sale Securities, Less than 12 months, Fair Value | $ 2,689 | $ 14,345
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 6 | $ 135
Number of investments, 12 months or longer | Investments | 23 | 13
Available-for-sale Securities, 12 months or longer, Fair Value | $ 22,814 | $ 14,597
Available-for-sale Securities, 12 months or Longer, Unrealized losses | $ 545 | $ 251
Number of investments, Total | Investments | 25 | 24
Available-for-sale Securities, Fair Value, Total | $ 25,503 | $ 29,940
Available-for-sale Securities, Unrealized Losses, Total | $ 551 | $ 386
Mortgage-backed [Member] | GNMA [Member] |  |
Summary of gross unrealized losses on investment securities and fair market value of related securities |  |
Number of investments, Less than 12 months | Investments | 1 | 2
Available-for-sale Securities, Less than 12 months, Fair Value | $ 1,104 | $ 2,270
Available-for-sale Securities, Less than 12 months, Unrealized losses | $ 6 | $ 40
Number of investments, 12 months or longer | Investments | 3 | 1
Available-for-sale Securities, 12 months or longer, Fair Value | $ 2,919 | $ 971
Available-for-sale Securities, 12 months or Longer, Unrealized losses | $ 126 | $ 42
Number of investments, Total | Investments | 4 | 3
Available-for-sale Securities, Fair Value, Total | $ 4,023 | $ 2,243
Available-for-sale Securities, Unrealized Losses, Total | $ 132 | $ 82

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