LOANS - Loans Accounted for on a Nonaccrual Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	$ 18,129	$ 17,952
Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	23,350	24,107
Commercial, financial and agricultural | Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	3,396	1,412
Commercial, financial and agricultural | Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	2,415	1,199
Real estate – construction and development | Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	1,136	892
Real estate – construction and development | Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	7,078	6,119
Real estate – commercial and farmland | Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	3,184	4,654
Real estate – commercial and farmland | Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	6,100	5,534
Real estate – residential | Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	9,996	10,465
Real estate – residential | Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	7,252	10,769
Consumer installment | Loans Excluding Purchased Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	417	529
Consumer installment | Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans	$ 505	$ 486