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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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