LOANS AND ALLOWANCE FOR LOAN LOSSES (Summary of Loans on Nonaccrual Status) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Jan. 01, 2021	Dec. 31, 2020	Jan. 01, 2020
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	$ 41,866	$ 42,448	$ 42,448	$ 45,204
Nonaccrual With No ALLL	12,792		11,497
Loans Past Due Over 90 Days Still Accruing	9,776		13,634
Construction and Land Development
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	2,637	3,072	3,072	4,060
Nonaccrual With No ALLL	1,985		1,985
Loans Past Due Over 90 Days Still Accruing	189		0
Commercial Real Estate - Owner Occupied
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	7,016	7,128	7,128	13,889
Nonaccrual With No ALLL	1,994		1,994
Loans Past Due Over 90 Days Still Accruing	3,180		3,727
Commercial Real Estate - Non-Owner Occupied
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	1,958	2,317	2,317	1,368
Nonaccrual With No ALLL	0		0
Loans Past Due Over 90 Days Still Accruing	817		148
Multifamily Real Estate
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	0	33	33	0
Nonaccrual With No ALLL	0		0
Loans Past Due Over 90 Days Still Accruing	0		0
Commercial and Industrial
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	2,023	2,107	2,107	3,037
Nonaccrual With No ALLL	1		1
Loans Past Due Over 90 Days Still Accruing	654		1,114
Residential 1-4 Family - Commercial
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	9,190	9,993	9,993	6,492
Nonaccrual With No ALLL	6,388		6,388
Loans Past Due Over 90 Days Still Accruing	576		1,560
Residential 1-4 Family - Consumer
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	14,770	12,600	12,600	13,117
Nonaccrual With No ALLL	2,364		1,069
Loans Past Due Over 90 Days Still Accruing	3,041		5,699
Residential 1-4 Family - Revolving
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	3,853	4,629	4,629	2,490
Nonaccrual With No ALLL	60		60
Loans Past Due Over 90 Days Still Accruing	917		826
Auto
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	303	500	500	565
Nonaccrual With No ALLL	0		0
Loans Past Due Over 90 Days Still Accruing	154		166
Consumer
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	116	$ 69	69	88
Nonaccrual With No ALLL	0		0
Loans Past Due Over 90 Days Still Accruing	248		394
Other Commercial
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual	0		0	$ 98
Nonaccrual With No ALLL			0
Loans Past Due Over 90 Days Still Accruing	$ 0		$ 0

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