Investment Securities (Details 2) $ in Thousands	12 Months Ended
Dec. 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	25	63
Available-for-sale Securities, Less than 12 months, Fair Value	$ 27,846	$ 47,809
Available-for-sale Securities, Less than 12 months, Unrealized losses	$ 245	$ 897
Number of investments, 12 months or longer \| Investment	28	2
Available-for-sale Securities, 12 months or longer, Fair Value	$ 27,511	$ 3,991
Available-for-sale Securities, 12 months or Longer, Unrealized losses	$ 518	$ 30
Number of investments, Total \| Investment	53	65
Available-for-sale Securities, Fair Value, Total	$ 55,357	$ 51,800
Available-for-sale Securities, Unrealized Losses, Total	$ 763	$ 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	5	5
Available-for-sale Securities, Less than 12 months, Fair Value	$ 4,184	$ 5,144
Available-for-sale Securities, Less than 12 months, Unrealized losses	$ 22	$ 113
Number of investments, 12 months or longer \| Investment	4
Available-for-sale Securities, 12 months or longer, Fair Value	$ 3,968
Available-for-sale Securities, 12 months or Longer, Unrealized losses	$ 75
Number of investments, Total \| Investment	9	5
Available-for-sale Securities, Fair Value, Total	$ 8,152	$ 5,144
Available-for-sale Securities, Unrealized Losses, Total	$ 97	$ 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	$ 2,936	$ 1,437
Available-for-sale Securities, Less than 12 months, Unrealized losses	$ 13	$ 16
Number of investments, 12 months or longer \| Investment	1
Available-for-sale Securities, 12 months or longer, Fair Value	$ 1,127
Available-for-sale Securities, 12 months or Longer, Unrealized losses	$ 11
Number of investments, Total \| Investment	2	1
Available-for-sale Securities, Fair Value, Total	$ 4,063	$ 1,437
Available-for-sale Securities, Unrealized Losses, Total	$ 24	$ 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	3	32
Available-for-sale Securities, Less than 12 months, Fair Value	$ 1,214	$ 13,936
Available-for-sale Securities, Less than 12 months, Unrealized losses	$ 9	$ 292
Number of investments, 12 months or longer \| Investment	2
Available-for-sale Securities, 12 months or longer, Fair Value	$ 792
Available-for-sale Securities, 12 months or Longer, Unrealized losses	$ 16
Number of investments, Total \| Investment	5	32
Available-for-sale Securities, Fair Value, Total	$ 2,006	$ 13,936
Available-for-sale Securities, Unrealized Losses, Total	$ 25	$ 292
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 \| Investment	3	10
Available-for-sale Securities, Less than 12 months, Fair Value	$ 2,897	$ 10,737
Available-for-sale Securities, Less than 12 months, Unrealized losses	$ 26	$ 185
Number of investments, 12 months or longer \| Investment	7
Available-for-sale Securities, 12 months or longer, Fair Value	$ 6,056
Available-for-sale Securities, 12 months or Longer, Unrealized losses	$ 123
Number of investments, Total \| Investment	10	10
Available-for-sale Securities, Fair Value, Total	$ 8,953	$ 10,737
Available-for-sale Securities, Unrealized Losses, Total	$ 149	$ 185
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 \| Investment	11	14
Available-for-sale Securities, Less than 12 months, Fair Value	$ 14,345	$ 15,478
Available-for-sale Securities, Less than 12 months, Unrealized losses	$ 135	$ 247
Number of investments, 12 months or longer \| Investment	13	2
Available-for-sale Securities, 12 months or longer, Fair Value	$ 14,597	$ 3,991
Available-for-sale Securities, 12 months or Longer, Unrealized losses	$ 251	$ 30
Number of investments, Total \| Investment	24	16
Available-for-sale Securities, Fair Value, Total	$ 29,940	$ 19,469
Available-for-sale Securities, Unrealized Losses, Total	$ 386	$ 277
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 \| Investment	2	1
Available-for-sale Securities, Less than 12 months, Fair Value	$ 2,270	$ 1,077
Available-for-sale Securities, Less than 12 months, Unrealized losses	$ 40	$ 44
Number of investments, 12 months or longer \| Investment	1
Available-for-sale Securities, 12 months or longer, Fair Value	$ 971
Available-for-sale Securities, 12 months or Longer, Unrealized losses	$ 42
Number of investments, Total \| Investment	3	1
Available-for-sale Securities, Fair Value, Total	$ 2,243	$ 1,077
Available-for-sale Securities, Unrealized Losses, Total	$ 82	$ 44

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