LOANS AND ALLOWANCE FOR CREDIT LOSSES - Loans Accounted for on a Nonaccrual Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, nonaccrual	$ 102,597	$ 85,266
Financing receivable, nonaccrual, no allowance	8,931	10,376
Commercial, financial and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, nonaccrual	13,198	14,214
Financing receivable, nonaccrual, no allowance	0	164
Consumer installment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, nonaccrual	561	476
Indirect automobile
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, nonaccrual	706	947
Premium finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, nonaccrual, no allowance	289	0
Real estate – construction and development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, nonaccrual	847	492
Financing receivable, nonaccrual, no allowance	304	209
Real estate – commercial and farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, nonaccrual	10,891	15,365
Financing receivable, nonaccrual, no allowance	3,553	2,061
Real estate – residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, nonaccrual	76,394	53,772
Financing receivable, nonaccrual, no allowance	$ 4,785	$ 7,942