Loans - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 1,244	$ 1,393
Collectively evaluated for impairment	11,256	10,501
Total ending allowance balance	12,500	11,894	$ 13,792	$ 13,837
Loans:
Individually evaluated for impairment	16,402	17,247
Collectively evaluated for impairment	1,331,639	1,337,110
Total	1,348,041	1,354,357
Commercial, financial, and agricultural
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	1,897	1,779
Total ending allowance balance	1,897	1,779	1,732	1,680
Loans:
Individually evaluated for impairment	2,025	2,285
Collectively evaluated for impairment	156,125	153,928
Total	158,150	156,213
Real Estate Mortgages \| Residential
Ending allowance balance attributable to loans:
Individually evaluated for impairment	177	211
Collectively evaluated for impairment	4,360	4,095
Total ending allowance balance	4,537	4,306	5,730	5,616
Loans:
Individually evaluated for impairment	5,730	6,176
Collectively evaluated for impairment	610,424	617,080
Total	616,154	623,256
Real Estate Mortgages \| Commercial
Ending allowance balance attributable to loans:
Individually evaluated for impairment	1,062	1,104
Collectively evaluated for impairment	2,352	2,106
Total ending allowance balance	3,414	3,210	3,802	4,047
Loans:
Individually evaluated for impairment	8,561	8,575
Collectively evaluated for impairment	352,176	354,686
Total	360,737	363,261
Real Estate Mortgages \| Construction
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	160	118
Total ending allowance balance	160	118	130	143
Loans:
Individually evaluated for impairment	65	65
Collectively evaluated for impairment	39,232	38,002
Total	39,297	38,067
Consumer automobile loans
Ending allowance balance attributable to loans:
Individually evaluated for impairment	5	62
Collectively evaluated for impairment	1,850	1,718
Total ending allowance balance	1,855	1,780	1,402	1,328
Loans:
Individually evaluated for impairment	21	130
Collectively evaluated for impairment	151,694	150,387
Total	151,715	150,517
Other consumer installment loans
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	16
Collectively evaluated for impairment	267	262
Total ending allowance balance	267	278	278	259
Loans:
Individually evaluated for impairment	0	16
Collectively evaluated for impairment	21,988	23,027
Total	21,988	23,043
Unallocated
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	370	423
Total ending allowance balance	$ 370	$ 423	$ 718	$ 764

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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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, before allowance for credit loss and fee, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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