Loans - Schedule of Loans on Nonaccrual Status (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans on nonaccrual status	$ 51,476	$ 49,278
Commercial, financial and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans on nonaccrual status	24,919	37,418
Real estate - construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans on nonaccrual status	599	66
Real estate – commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans on nonaccrual status	23,468	11,128
Real estate - residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans on nonaccrual status	2,450	618
Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans on nonaccrual status	$ 40	$ 48