LOANS - Additional Detail of Impaired Loans Broken Out According to Class (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Impaired loans with no a related allowance, Recorded Investment	$ 6,619	$ 14,178	$ 7,595
Impaired loans with no related allowance, Unpaid Balance	6,869	14,348	9,639
Impaired loans with no related allowance, Related Allowance	0	0	0
Impaired loans with no related allowance, Average Recorded Investment YTD	12,438	12,963	12,668
Impaired loans with no related allowance, Interest Income Recognized YTD	52	598	526
Impaired loans with a related allowance, Recorded Investment	20,776	15,761	5,846
Impaired loans with a related allowance, Unpaid Balance	21,072	15,914	5,864
Impaired loans with a related allowance, Related Allowance	5,669	4,424	1,179
Impaired loans with a related allowance, Average Recorded Investment YTD	16,693	12,789	4,415
Impaired loans with a related allowance, Interest Income Recognized YTD	98	67	195
Recorded Investment	27,395	29,939	13,459
Unpaid Balance	27,941	30,262	15,503
Related Allowance	5,669	4,424	1,179
Average Recorded Investment YTD	29,131	25,752	17,083
Interest Income Recognized YTD	150	665	721
Commercial, financial and agricultural
Financing Receivable, Impaired [Line Items]
Impaired loans with no a related allowance, Recorded Investment	0	59	709
Impaired loans with no related allowance, Unpaid Balance	0	62	709
Impaired loans with no related allowance, Related Allowance	0	0	0
Impaired loans with no related allowance, Average Recorded Investment YTD	198	294	379
Impaired loans with no related allowance, Interest Income Recognized YTD	0	7	27
Impaired loans with a related allowance, Recorded Investment	2,241	2,434	960
Impaired loans with a related allowance, Unpaid Balance	2,254	2,434	960
Impaired loans with a related allowance, Related Allowance	1,235	1,182	329
Impaired loans with a related allowance, Average Recorded Investment YTD	2,186	2,039	968
Impaired loans with a related allowance, Interest Income Recognized YTD	58	13	3
Recorded Investment	2,241	2,493	1,669
Unpaid Balance	2,254	2,496	1,669
Related Allowance	1,235	1,182	329
Average Recorded Investment YTD	2,384	2,333	1,347
Interest Income Recognized YTD	58	20	30
Commercial real estate
Financing Receivable, Impaired [Line Items]
Impaired loans with no a related allowance, Recorded Investment	5,884	13,556	6,441
Impaired loans with no related allowance, Unpaid Balance	6,087	13,671	8,170
Impaired loans with no related allowance, Related Allowance	0	0	0
Impaired loans with no related allowance, Average Recorded Investment YTD	11,433	10,473	7,685
Impaired loans with no related allowance, Interest Income Recognized YTD	47	591	427
Impaired loans with a related allowance, Recorded Investment	17,973	12,428	4,512
Impaired loans with a related allowance, Unpaid Balance	18,248	12,563	4,512
Impaired loans with a related allowance, Related Allowance	4,244	3,021	758
Impaired loans with a related allowance, Average Recorded Investment YTD	13,687	10,026	2,868
Impaired loans with a related allowance, Interest Income Recognized YTD	36	49	176
Recorded Investment	23,857	25,984	10,953
Unpaid Balance	24,335	26,234	12,682
Related Allowance	4,244	3,021	758
Average Recorded Investment YTD	25,120	20,499	10,553
Interest Income Recognized YTD	83	640	603
Consumer real estate \| Consumer
Financing Receivable, Impaired [Line Items]
Impaired loans with no a related allowance, Recorded Investment	712	542	445
Impaired loans with no related allowance, Unpaid Balance	758	594	760
Impaired loans with no related allowance, Related Allowance	0	0	0
Impaired loans with no related allowance, Average Recorded Investment YTD	790	2,173	4,522
Impaired loans with no related allowance, Interest Income Recognized YTD	5	0	69
Impaired loans with a related allowance, Recorded Investment	536	639	366
Impaired loans with a related allowance, Unpaid Balance	544	657	366
Impaired loans with a related allowance, Related Allowance	176	141	66
Impaired loans with a related allowance, Average Recorded Investment YTD	734	560	555
Impaired loans with a related allowance, Interest Income Recognized YTD	4	3	16
Recorded Investment	1,248	1,181	811
Unpaid Balance	1,302	1,251	1,126
Related Allowance	176	141	66
Average Recorded Investment YTD	1,524	2,733	5,077
Interest Income Recognized YTD	9	3	85
Consumer installment \| Consumer
Financing Receivable, Impaired [Line Items]
Impaired loans with no a related allowance, Recorded Investment	23	21	0
Impaired loans with no related allowance, Unpaid Balance	24	21	0
Impaired loans with no related allowance, Related Allowance	0	0	0
Impaired loans with no related allowance, Average Recorded Investment YTD	17	23	82
Impaired loans with no related allowance, Interest Income Recognized YTD	0	0	3
Impaired loans with a related allowance, Recorded Investment	26	260	26
Impaired loans with a related allowance, Unpaid Balance	26	260	26
Impaired loans with a related allowance, Related Allowance	14	80	26
Impaired loans with a related allowance, Average Recorded Investment YTD	86	164	24
Impaired loans with a related allowance, Interest Income Recognized YTD	0	2	0
Recorded Investment	49	281	26
Unpaid Balance	50	281	26
Related Allowance	14	80	26
Average Recorded Investment YTD	103	187	106
Interest Income Recognized YTD	$ 0	$ 2	$ 3

Amount of allowance for credit losses related to recorded investment.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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