LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Information Pertaining to Impaired Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	$ 99,676	$ 123,082
Allowance for Credit Losses	21,146	24,656
Commercial, financial and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	3,246	5,490
Allowance for Credit Losses	889	2,252
Premium finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	258	3,523
Allowance for Credit Losses	0	0
Real estate – construction and development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	2,244	4,173
Allowance for Credit Losses	693	512
Real estate – commercial and farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	83,000	100,180
Allowance for Credit Losses	18,494	21,001
Real estate – residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	10,928	9,716
Allowance for Credit Losses	$ 1,070	$ 891