Other Real Estate - Other Real Estate, By Geographic Location (Details) - USD ($) $ in Thousands		Dec. 31, 2017	Dec. 31, 2016		Dec. 31, 2015	[1]	Dec. 31, 2014	[1]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate		$ 43,228	$ 62,051	[1]	$ 78,828		$ 98,569
Alabama [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate		11,714	15,989
Florida [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate		13,937	22,582
Mississippi [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	[2]	14,260	15,646
Tennessee [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	[3]	2,535	6,183
Texas [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate		$ 782	$ 1,651

[1] The changes and gains, net on other real estate for the years ended December 31, 2016 and 2015 include covered other real estate.

[2] Mississippi includes Central and Southern Mississippi Regions

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