Loans - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Impaired loans
Impaired loans, troubled debt restructurings	$ 4,680	$ 5,450
Impaired loans, Unpaid Principal Balance	5,679	5,928
Impaired loans, Recorded Investment in Loans without Specific Reserve	1,743	2,842
Impaired loans, Recorded Investment in Loans with Specific Reserve	3,785	2,935,000
Impaired loans, Related Allowance	507	428
Impaired loans, Average Balance	5,650	6,099
Impaired loans, Interest Income Recognized	65	276
Real estate - residential mortgage
Impaired loans
Impaired loans, Unpaid Principal Balance	3,134	3,057
Impaired loans, Recorded Investment in Loans without Specific Reserve	1,273	1,288
Impaired loans, Recorded Investment in Loans with Specific Reserve	1,760	1,677,000
Impaired loans, Related Allowance	127	92
Impaired loans, Average Balance	3,099	3,056
Impaired loans, Interest Income Recognized	35	142
Commercial, financial and agricultural \| Commercial real estate lending
Impaired loans
Impaired loans, Unpaid Principal Balance	1,752	2,468
Impaired loans, Recorded Investment in Loans without Specific Reserve	3	1,498
Impaired loans, Recorded Investment in Loans with Specific Reserve	1,710	927,000
Impaired loans, Related Allowance	69	10
Impaired loans, Average Balance	1,768	2,653
Impaired loans, Interest Income Recognized	23	132
Commercial, financial and agricultural \| Builder line lending
Impaired loans
Impaired loans, Unpaid Principal Balance	437
Impaired loans, Recorded Investment in Loans without Specific Reserve	437
Impaired loans, Average Balance	437
Impaired loans, Interest Income Recognized	7
Commercial, financial and agricultural \| Commercial business lending
Impaired loans
Impaired loans, Unpaid Principal Balance		33
Impaired loans, Recorded Investment in Loans without Specific Reserve		25
Impaired loans, Average Balance		26
Equity lines
Impaired loans
Impaired loans, Unpaid Principal Balance	225	365
Impaired loans, Recorded Investment in Loans without Specific Reserve	30	31
Impaired loans, Recorded Investment in Loans with Specific Reserve	187	326,000
Impaired loans, Related Allowance	187	326
Impaired loans, Average Balance	217	359
Impaired loans, Interest Income Recognized		2
Consumer
Impaired loans
Impaired loans, Unpaid Principal Balance	131	5
Impaired loans, Recorded Investment in Loans with Specific Reserve	128	5,000
Impaired loans, Related Allowance	124
Impaired loans, Average Balance	$ 129	$ 5

Financing Receivables Impaired Troubled Debt Restructuring Amount

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- Definition

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+ References

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- Definition

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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+ 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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