LOANS - Deferrals Loans (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Financing Receivable, Troubled Debt Restructuring [Line Items]
COVID-19 Deferrals	$ 648,516
Deferrals as a % of total loans	4.30%
Commercial, financial and agricultural
Financing Receivable, Troubled Debt Restructuring [Line Items]
COVID-19 Deferrals	$ 49,526
Deferrals as a % of total loans	2.60%
Consumer installment
Financing Receivable, Troubled Debt Restructuring [Line Items]
COVID-19 Deferrals	$ 2,421
Deferrals as a % of total loans	0.50%
Indirect automobile
Financing Receivable, Troubled Debt Restructuring [Line Items]
COVID-19 Deferrals	$ 11,042
Deferrals as a % of total loans	1.60%
Real estate – construction and development
Financing Receivable, Troubled Debt Restructuring [Line Items]
COVID-19 Deferrals	$ 42,915
Deferrals as a % of total loans	2.60%
Real estate – commercial and farmland
Financing Receivable, Troubled Debt Restructuring [Line Items]
COVID-19 Deferrals	$ 368,607
Deferrals as a % of total loans	7.20%
Real estate – residential
Financing Receivable, Troubled Debt Restructuring [Line Items]
COVID-19 Deferrals	$ 174,005
Deferrals as a % of total loans	6.30%