Non Purchased Loans - Investment and Interest Income Recognized on Impaired Loans (Details) - Non purchased loans and leases - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Investment and interest income recognized on impaired loans
Average Recorded Investment	$ 40,858	$ 26,216	$ 40,517	$ 26,688
Interest Income Recognized	207	142	620	433
Commercial, financial, agricultural
Investment and interest income recognized on impaired loans
Average Recorded Investment	5,705	1,979	5,656	2,204
Interest Income Recognized	5	11	23	31
Lease financing
Investment and interest income recognized on impaired loans
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Real estate – construction
Investment and interest income recognized on impaired loans
Average Recorded Investment	12,128	9,725	11,756	9,621
Interest Income Recognized	111	42	321	109
Real estate – 1-4 family mortgage
Investment and interest income recognized on impaired loans
Average Recorded Investment	12,203	8,136	12,323	8,388
Interest Income Recognized	50	51	153	174
Real estate – commercial mortgage
Investment and interest income recognized on impaired loans
Average Recorded Investment	10,692	6,258	10,652	6,354
Interest Income Recognized	41	37	122	117
Installment loans to individuals
Investment and interest income recognized on impaired loans
Average Recorded Investment	130	118	130	121
Interest Income Recognized	$ 0	$ 1	$ 1	$ 2