LOAN CREDIT QUALITY AND RELATED ALLOWANCE FOR LOAN LOSSES - Aging Category of Loans, by Segment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Aging categories of loans by segment
Current	$ 1,334,612	$ 1,355,315
Past Due 30 To 89 Days	7,324	12,006
Past Due 90 Days Or More & Still Accruing	2,047	1,274
Non-Accrual	10,374	15,298
Total ending loans balance	1,354,357	1,383,893
Net deferred loan fees and discounts	1,187	864
Allowance for loan losses	(11,894)	(13,837)	$ (12,858)	$ (12,896)
Current loans, net	1,323,905	1,342,342
Loans, net	1,343,650	1,370,920
Commercial, Financial, and Agricultural Portfolio Segment
Aging categories of loans by segment
Current	153,737	182,651
Past Due 30 To 89 Days	249	616
Past Due 90 Days Or More & Still Accruing	30	0
Non-Accrual	2,197	5,294
Total ending loans balance	156,213	188,561
Allowance for loan losses	(1,779)	(1,680)	(1,177)	(1,554)
Consumer automobile loans
Aging categories of loans by segment
Current	149,703	132,713
Past Due 30 To 89 Days	709	412
Past Due 90 Days Or More & Still Accruing	0	27
Non-Accrual	105	31
Total ending loans balance	150,517	133,183
Allowance for loan losses	(1,780)	(1,328)	(804)	(143)
Other consumer installment loans
Aging categories of loans by segment
Current	22,124	23,902
Past Due 30 To 89 Days	579	636
Past Due 90 Days Or More & Still Accruing	324	9
Non-Accrual	16	5
Total ending loans balance	23,043	24,552
Allowance for loan losses	(278)	(259)	(271)	(273)
Residential Real Estate Mortgage \| Real Estate Mortgage Portfolio Segment
Aging categories of loans by segment
Current	615,580	611,281
Past Due 30 To 89 Days	4,881	7,688
Past Due 90 Days Or More & Still Accruing	1,529	1,238
Non-Accrual	1,266	2,172
Total ending loans balance	623,256	622,379
Allowance for loan losses	(4,306)	(5,616)	(5,679)	(5,383)
Commercial Real Estate Mortgage \| Real Estate Mortgage Portfolio Segment
Aging categories of loans by segment
Current	355,597	361,624
Past Due 30 To 89 Days	775	2,349
Past Due 90 Days Or More & Still Accruing	164	0
Non-Accrual	6,725	7,722
Total ending loans balance	363,261	371,695
Allowance for loan losses	(3,210)	(4,047)	(4,277)	(4,975)
Construction Real Estate Mortgage \| Real Estate Mortgage Portfolio Segment
Aging categories of loans by segment
Current	37,871	43,144
Past Due 30 To 89 Days	131	305
Past Due 90 Days Or More & Still Accruing	0	0
Non-Accrual	65	74
Total ending loans balance	38,067	43,523
Allowance for loan losses	$ (118)	$ (143)	$ (155)	$ (178)

Represents the financing receivables that are less than 90 days past due but more than 29 days past due.

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Amount of financing receivable 90 days or more past due and still accruing.

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Amount of financing receivable not past due.

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Amount of financing receivable on nonaccrual status.

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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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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount, after allowance for credit loss, of financing receivable, classified as current. Includes, but is not limited to, notes and loan receivable.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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