Investment Securities Available-for-sale and held-to-maturity securities (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Available-for-sale Securities
Amortized Cost	$ 63,586
Amortized Cost	64,086	$ 66,561
Gross Unrealized Gains	474	239
Gross Unrealized Losses	(590)	(1,244)
Fair Value	63,470
Investment securities available-for-sale	63,970	65,556
Held-to-maturity Securities [Abstract]
Amortized Cost	1,000	999
Fair Value	999	999
US Government-sponsored enterprises [Member]
Available-for-sale Securities
Amortized Cost	9,535	10,221
Gross Unrealized Gains	18	15
Gross Unrealized Losses	(143)	(196)
Fair Value	9,410	10,040
Investment securities available-for-sale	9,410	10,040
Held-to-maturity Securities [Abstract]
Amortized Cost	1,000	999
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	0
Fair Value	999	999
Agency mortgage-backed [Member]
Available-for-sale Securities
Amortized Cost	18,820	18,283
Gross Unrealized Gains	47	27
Gross Unrealized Losses	(126)	(269)
Fair Value	18,741	18,041
Investment securities available-for-sale	18,741	18,041
State and political subdivisions [Member]
Available-for-sale Securities
Amortized Cost	25,304	27,909
Gross Unrealized Gains	259	113
Gross Unrealized Losses	(249)	(650)
Fair Value	25,314	27,372
Investment securities available-for-sale	25,314	27,372
Corporate [Member]
Available-for-sale Securities
Amortized Cost	9,927	9,745
Gross Unrealized Gains	150	84
Gross Unrealized Losses	(72)	(129)
Fair Value	10,005	9,700
Investment securities available-for-sale	10,005	9,700
Total debt securities [Member]
Available-for-sale Securities
Amortized Cost	63,586	66,158
Gross Unrealized Gains	474	239
Gross Unrealized Losses	(590)	(1,244)
Fair Value	63,470	65,153
Investment securities available-for-sale	63,470	65,153
Mutual funds [Member]
Available-for-sale Securities
Mutual Funds, Amortized Cost	500	403
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Mutual Funds, Fair Value	500	403
Investment securities available-for-sale	$ 500	$ 403

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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