Investment Securities (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Available for sale
Total investment securities available for sale, Amortized Cost	$ 71,795	$ 68,181
Total investment securities available for sale, Gross Unrealized Gains	56	185
Total investment securities available for sale, Gross Unrealized Losses	1,784	763
Available-for-sale securities, investment securities, Fair Value	70,067	67,603
US government agencies [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	8,987	8,749
Total investment securities available for sale, Gross Unrealized Gains	1	1
Total investment securities available for sale, Gross Unrealized Losses	274	97
Available-for-sale securities, investment securities, Fair Value	8,714	8,653
SBA securities [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	3,904	4,087
Total investment securities available for sale, Gross Unrealized Gains
Total investment securities available for sale, Gross Unrealized Losses	135	24
Available-for-sale securities, investment securities, Fair Value	3,769	4,063
State and political subdivisions [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	8,530	11,242
Total investment securities available for sale, Gross Unrealized Gains	49	179
Total investment securities available for sale, Gross Unrealized Losses	107	25
Available-for-sale securities, investment securities, Fair Value	8,472	11,396
Asset-backed securities [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	6,703
Total investment securities available for sale, Gross Unrealized Gains	3
Total investment securities available for sale, Gross Unrealized Losses	15
Available-for-sale securities, investment securities, Fair Value	6,691
Mortgage-backed securities [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	43,671	44,103
Total investment securities available for sale, Gross Unrealized Gains	3	5
Total investment securities available for sale, Gross Unrealized Losses	1,253	617
Available-for-sale securities, investment securities, Fair Value	42,421	43,491
Mortgage-backed securities [Member] \| FHLMC [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	8,401	9,102
Total investment securities available for sale, Gross Unrealized Gains
Total investment securities available for sale, Gross Unrealized Losses	327	149
Available-for-sale securities, investment securities, Fair Value	8,074	8,953
Mortgage-backed securities [Member] \| FNMA [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	32,089	29,383
Total investment securities available for sale, Gross Unrealized Gains	2	3
Total investment securities available for sale, Gross Unrealized Losses	780	386
Available-for-sale securities, investment securities, Fair Value	31,311	29,000
Mortgage-backed securities [Member] \| GNMA [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	3,181	5,618
Total investment securities available for sale, Gross Unrealized Gains	1	2
Total investment securities available for sale, Gross Unrealized Losses	146	82
Available-for-sale securities, investment securities, Fair Value	$ 3,036	$ 5,538

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 320
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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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