LOANS - Analysis of Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Contractual Principal Balance	$ 37,224	$ 29,676	$ 29,193	$ 37,224	$ 29,193	$ 29,676
Recorded Investment With No Allowance	7,579	8,324	8,143	7,579	8,143	8,324
Recorded Investment With Allowance	27,590	18,951	18,786	27,590	18,786	18,951
Total Recorded Investment	35,169	27,275	26,929	35,169	26,929	27,275
Related Allowance	3,727	2,465	2,632	3,727	2,632	2,465
Average recorded investment	33,125	25,805	27,384	30,656	26,408	26,063
Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Contractual Principal Balance	134,577	59,562	69,427	134,577	69,427	59,562
Recorded Investment With No Allowance	67,442	10,882	12,836	67,442	12,836	10,882
Recorded Investment With Allowance	29,615	31,965	35,291	29,615	35,291	31,965
Total Recorded Investment	97,057	42,847	48,127	97,057	48,127	42,847
Related Allowance	1,525	1,933	2,013	1,525	2,013	1,933
Average recorded investment	97,057	45,488	43,732	70,063	39,988	40,559
Commercial, financial and agricultural | Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Contractual Principal Balance	4,242	1,902	2,216	4,242	2,216	1,902
Recorded Investment With No Allowance	773	1,155	966	773	966	1,155
Recorded Investment With Allowance	2,979	513	838	2,979	838	513
Total Recorded Investment	3,752	1,668	1,804	3,752	1,804	1,668
Related Allowance	1,569	4	5	1,569	5	4
Average recorded investment	3,724	1,736	1,791	2,645	1,629	1,637
Commercial, financial and agricultural | Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Contractual Principal Balance	16,132	5,717	5,499	16,132	5,499	5,717
Recorded Investment With No Allowance	3,445	473	631	3,445	631	473
Recorded Investment With Allowance	1,956	757	341	1,956	341	757
Total Recorded Investment	5,401	1,230	972	5,401	972	1,230
Related Allowance	54	0	0	54	0	0
Average recorded investment	5,401	1,101	670	3,980	737	836
Real estate – construction and development | Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Contractual Principal Balance	2,019	1,378	1,444	2,019	1,444	1,378
Recorded Investment With No Allowance	505	613	720	505	720	613
Recorded Investment With Allowance	921	424	701	921	701	424
Total Recorded Investment	1,426	1,037	1,421	1,426	1,421	1,037
Related Allowance	113	3	46	113	46	3
Average recorded investment	1,350	1,229	1,110	1,280	971	984
Real estate – construction and development | Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Contractual Principal Balance	13,256	13,714	16,066	13,256	16,066	13,714
Recorded Investment With No Allowance	169	623	312	169	312	623
Recorded Investment With Allowance	6,035	6,511	7,033	6,035	7,033	6,511
Total Recorded Investment	6,204	7,134	7,345	6,204	7,345	7,134
Related Allowance	262	476	255	262	255	476
Average recorded investment	6,204	7,240	6,561	6,622	5,356	5,712
Real estate – commercial and farmland | Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Contractual Principal Balance	6,991	8,950	8,911	6,991	8,911	8,950
Recorded Investment With No Allowance	593	867	536	593	536	867
Recorded Investment With Allowance	5,783	6,649	7,021	5,783	7,021	6,649
Total Recorded Investment	6,376	7,516	7,557	6,376	7,557	7,516
Related Allowance	488	1,591	1,799	488	1,799	1,591
Average recorded investment	6,235	7,537	8,186	6,610	7,969	7,879
Real estate – commercial and farmland | Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Contractual Principal Balance	38,382	14,766	20,297	38,382	20,297	14,766
Recorded Investment With No Allowance	14,629	1,115	3,013	14,629	3,013	1,115
Recorded Investment With Allowance	9,977	10,581	12,319	9,977	12,319	10,581
Total Recorded Investment	24,606	11,696	15,332	24,606	15,332	11,696
Related Allowance	555	684	872	555	872	684
Average recorded investment	24,606	13,514	13,282	18,018	12,513	12,349
Real estate – residential | Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Contractual Principal Balance	23,476	16,885	15,964	23,476	15,964	16,885
Recorded Investment With No Allowance	5,234	5,144	5,298	5,234	5,298	5,144
Recorded Investment With Allowance	17,907	11,365	10,226	17,907	10,226	11,365
Total Recorded Investment	23,141	16,509	15,524	23,141	15,524	16,509
Related Allowance	1,557	867	782	1,557	782	867
Average recorded investment	21,365	14,719	15,726	19,650	15,308	15,029
Real estate – residential | Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Contractual Principal Balance	63,328	24,839	27,028	63,328	27,028	24,839
Recorded Investment With No Allowance	48,469	8,185	8,393	48,469	8,393	8,185
Recorded Investment With Allowance	11,647	14,116	15,598	11,647	15,598	14,116
Total Recorded Investment	60,116	22,301	23,991	60,116	23,991	22,301
Related Allowance	654	773	886	654	886	773
Average recorded investment	60,116	23,146	22,932	40,808	21,217	21,433
Consumer installment | Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Contractual Principal Balance	496	561	658	496	658	561
Recorded Investment With No Allowance	474	545	623	474	623	545
Recorded Investment With Allowance	0	0	0	0	0	0
Total Recorded Investment	474	545	623	474	623	545
Related Allowance	0	0	0	0	0	0
Average recorded investment	451	584	571	471	531	534
Consumer installment | Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Contractual Principal Balance	3,479	526	537	3,479	537	526
Recorded Investment With No Allowance	730	486	487	730	487	486
Recorded Investment With Allowance	0	0	0	0	0	0
Total Recorded Investment	730	486	487	730	487	486
Related Allowance	0	0	0	0	0	0
Average recorded investment	$ 730	$ 487	$ 287	$ 635	$ 165	$ 229