Loans - Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Impaired loans
Impaired loans, troubled debt restructurings	$ 5,450
Impaired loans, Unpaid Principal Balance	5,928	$ 11,120
Impaired loans, Recorded Investment in Loans without Specific Reserve	2,842	4,832
Impaired loans, Recorded Investment in Loans with Specific Reserve	2,935	6,064
Impaired loans, Related Allowance	428	829
Impaired loans, Average Balance	6,099	11,959
Impaired loans, Interest Income Recognized	276	367
Real estate - residential mortgage
Impaired loans
Impaired loans, Unpaid Principal Balance	3,057	3,745
Impaired loans, Recorded Investment in Loans without Specific Reserve	1,288	1,603
Impaired loans, Recorded Investment in Loans with Specific Reserve	1,677	2,033
Impaired loans, Related Allowance	92	214
Impaired loans, Average Balance	3,056	3,743
Impaired loans, Interest Income Recognized	142	184
Commercial, financial and agricultural \| Commercial real estate lending
Impaired loans
Impaired loans, Unpaid Principal Balance	2,468	6,981
Impaired loans, Recorded Investment in Loans without Specific Reserve	1,498	2,841
Impaired loans, Recorded Investment in Loans with Specific Reserve	927	4,031
Impaired loans, Related Allowance	10	615
Impaired loans, Average Balance	2,653	7,818
Impaired loans, Interest Income Recognized	132	168
Commercial, financial and agricultural \| Commercial business lending
Impaired loans
Impaired loans, Unpaid Principal Balance	33	41
Impaired loans, Recorded Investment in Loans without Specific Reserve	25	35
Impaired loans, Average Balance	26	45
Equity lines
Impaired loans
Impaired loans, Unpaid Principal Balance	365	32
Impaired loans, Recorded Investment in Loans without Specific Reserve	31	31
Impaired loans, Recorded Investment in Loans with Specific Reserve	326
Impaired loans, Related Allowance	326
Impaired loans, Average Balance	359	32
Impaired loans, Interest Income Recognized	2	2
Consumer Loan
Impaired loans
Impaired loans, Unpaid Principal Balance	5	321
Impaired loans, Recorded Investment in Loans without Specific Reserve		322
Impaired loans, Recorded Investment in Loans with Specific Reserve	5
Impaired loans, Average Balance	$ 5	321
Impaired loans, Interest Income Recognized		$ 13

Financing Receivables Impaired Troubled Debt Restructuring Amount

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of allowance for credit losses related to recorded investment.

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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