Loans and Allowance for Loan Losses - Impairment Methodology (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for loan losses:
Individually evaluated for impairment	$ 615	$ 1,194
Collectively evaluated for impairment	11,862	10,458
Total	12,477	11,652	$ 10,852	$ 9,886
Loans outstanding:
Individually evaluated for impairment	7,395	8,478
Collectively evaluated for impairment	1,161,830	1,138,149
Total	1,169,225	1,146,627
Commercial, financial, and agricultural
Allowance for loan losses:
Individually evaluated for impairment	311	551
Collectively evaluated for impairment	2,607	2,686
Total	2,918	3,237	3,325	2,753
Loans outstanding:
Individually evaluated for impairment	1,514	2,428
Collectively evaluated for impairment	197,508	205,292
Total	199,022	207,720
Residential real estate \| Construction
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	64	140
Total	64	140	170	108
Loans outstanding:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	23,035	28,610
Total	23,035	28,610
Residential real estate \| Mortgages
Allowance for loan losses:
Individually evaluated for impairment	264	579
Collectively evaluated for impairment	1,854	1,492
Total	2,118	2,071	1,689	2,385
Loans outstanding:
Individually evaluated for impairment	3,856	4,793
Collectively evaluated for impairment	249,215	236,724
Total	253,071	241,517
Commercial real estate \| Construction
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	369	757
Total	369	757	807	413
Loans outstanding:
Individually evaluated for impairment	137	153
Collectively evaluated for impairment	84,861	106,631
Total	84,998	106,784
Commercial real estate \| Mortgages
Allowance for loan losses:
Individually evaluated for impairment	23	37
Collectively evaluated for impairment	6,524	4,877
Total	6,547	4,914	4,437	3,793
Loans outstanding:
Individually evaluated for impairment	1,711	850
Collectively evaluated for impairment	574,924	528,686
Total	576,635	529,536
Installment and other consumer
Allowance for loan losses:
Individually evaluated for impairment	17	27
Collectively evaluated for impairment	364	307
Total	381	334	345	274
Loans outstanding:
Individually evaluated for impairment	177	254
Collectively evaluated for impairment	32,287	32,206
Total	32,464	32,460
Unallocated
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	80	199
Total	80	199	$ 79	$ 160
Loans outstanding:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	0	0
Total	$ 0	$ 0

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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