Other Real Estate - Other Real Estate, By Geographic Location (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016
Other real estate, excluding covered other real estate [Line Items]
Total other real estate		$ 36,475	$ 43,228	$ 48,356	$ 62,051
Alabama [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate		7,526	11,714
Florida [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate		8,931	13,937
Mississippi [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	[1]	18,191	14,260
Tennessee [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	[2]	1,083	2,535
Texas [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate		$ 744	$ 782

[1] Mississippi includes Central and Southern Mississippi Regions

[2] Tennessee includes Memphis, Tennessee and Northern Mississippi Regions