Investment Securities (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Available for sale
Total investment securities available for sale, Amortized Cost	$ 60,002	$ 68,181
Total investment securities available for sale, Gross Unrealized Gains	58	185
Total investment securities available for sale, Gross Unrealized Losses	1,554	763
Available-for-sale securities, investment securities, Fair Value	58,506	67,603
US government agencies [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	7,743	8,749
Total investment securities available for sale, Gross Unrealized Gains	1	1
Total investment securities available for sale, Gross Unrealized Losses	214	97
Available-for-sale securities, investment securities, Fair Value	7,530	8,653
SBA securities [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	3,925	4,087
Total investment securities available for sale, Gross Unrealized Gains
Total investment securities available for sale, Gross Unrealized Losses	100	24
Available-for-sale securities, investment securities, Fair Value	3,825	4,063
State and political subdivisions [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	6,388	11,242
Total investment securities available for sale, Gross Unrealized Gains	54	179
Total investment securities available for sale, Gross Unrealized Losses	94	25
Available-for-sale securities, investment securities, Fair Value	6,348	11,396
Mortgage-backed securities [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	41,946	44,103
Total investment securities available for sale, Gross Unrealized Gains	3	5
Total investment securities available for sale, Gross Unrealized Losses	1,146	617
Available-for-sale securities, investment securities, Fair Value	40,803	43,491
Mortgage-backed securities [Member] \| FHLMC [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	8,771	9,102
Total investment securities available for sale, Gross Unrealized Gains
Total investment securities available for sale, Gross Unrealized Losses	295	149
Available-for-sale securities, investment securities, Fair Value	8,476	8,953
Mortgage-backed securities [Member] \| FNMA [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	27,798	29,383
Total investment securities available for sale, Gross Unrealized Gains	2	3
Total investment securities available for sale, Gross Unrealized Losses	702	386
Available-for-sale securities, investment securities, Fair Value	27,098	29,000
Mortgage-backed securities [Member] \| GNMA [Member]
Available for sale
Total investment securities available for sale, Amortized Cost	5,377	5,618
Total investment securities available for sale, Gross Unrealized Gains	1	2
Total investment securities available for sale, Gross Unrealized Losses	149	82
Available-for-sale securities, investment securities, Fair Value	$ 5,229	$ 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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Amount of debt securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 320
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-Section 45
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-Section 50
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-Name Accounting Standards Codification
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-Paragraph 2
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+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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