Loans and the Allowance for Loan Losses - (Details 3) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Investment and interest income recognized on impaired loans
Average Recorded Investment	$ 139,016	$ 107,331	$ 140,360	$ 114,093
Interest Income Recognized	209	4,187	3,878	4,293
Commercial, financial, agricultural
Investment and interest income recognized on impaired loans
Average Recorded Investment	6,763	4,167	6,519	4,399
Interest Income Recognized	10	160	184	165
Lease financing
Investment and interest income recognized on impaired loans
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Real estate – construction
Investment and interest income recognized on impaired loans
Average Recorded Investment	0	1,997	0	2,023
Interest Income Recognized	0	96	0	98
Real estate – 1-4 family mortgage
Investment and interest income recognized on impaired loans
Average Recorded Investment	40,410	26,378	40,203	27,122
Interest Income Recognized	46	808	917	843
Real estate – commercial mortgage
Investment and interest income recognized on impaired loans
Average Recorded Investment	91,323	74,648	93,107	80,402
Interest Income Recognized	152	3,110	2,764	3,174
Installment loans to individuals
Investment and interest income recognized on impaired loans
Average Recorded Investment	520	141	531	147
Interest Income Recognized	$ 1	$ 13	$ 13	$ 13