Loans - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 2,228	$ 2,543
Collectively evaluated for impairment	11,564	11,294
Total ending allowance balance	13,792	13,837	$ 12,836	$ 12,858
Loans:
Individually evaluated for impairment	20,107	21,247
Collectively evaluated for impairment	1,363,417	1,362,646
Total	1,383,524	1,383,893
Commercial, financial, and agricultural
Ending allowance balance attributable to loans:
Individually evaluated for impairment	644	650
Collectively evaluated for impairment	1,088	1,030
Total ending allowance balance	1,732	1,680	1,372	1,177
Loans:
Individually evaluated for impairment	5,342	5,263
Collectively evaluated for impairment	189,575	183,298
Total	194,917	188,561
Real Estate Mortgages \| Residential
Ending allowance balance attributable to loans:
Individually evaluated for impairment	286	168
Collectively evaluated for impairment	5,444	5,448
Total ending allowance balance	5,730	5,616	5,656	5,679
Loans:
Individually evaluated for impairment	4,115	4,210
Collectively evaluated for impairment	614,444	618,169
Total	618,559	622,379
Real Estate Mortgages \| Commercial
Ending allowance balance attributable to loans:
Individually evaluated for impairment	1,253	1,720
Collectively evaluated for impairment	2,549	2,327
Total ending allowance balance	3,802	4,047	4,003	4,277
Loans:
Individually evaluated for impairment	10,474	11,664
Collectively evaluated for impairment	356,615	360,031
Total	367,089	371,695
Real Estate Mortgages \| Construction
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	130	143
Total ending allowance balance	130	143	156	155
Loans:
Individually evaluated for impairment	72	74
Collectively evaluated for impairment	39,209	43,449
Total	39,281	43,523
Consumer automobile loans
Ending allowance balance attributable to loans:
Individually evaluated for impairment	32	0
Collectively evaluated for impairment	1,370	1,328
Total ending allowance balance	1,402	1,328	1,016	804
Loans:
Individually evaluated for impairment	73	31
Collectively evaluated for impairment	139,764	133,152
Total	139,837	133,183
Other consumer installment loans
Ending allowance balance attributable to loans:
Individually evaluated for impairment	13	5
Collectively evaluated for impairment	265	254
Total ending allowance balance	278	259	305	271
Loans:
Individually evaluated for impairment	31	5
Collectively evaluated for impairment	23,810	24,547
Total	23,841	24,552
Unallocated
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	718	764
Total ending allowance balance	$ 718	$ 764	$ 328	$ 495

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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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The balance of financing receivables that were individually 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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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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