Other Real Estate - Other Real Estate, By Type of Property (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
Construction, Land Development And Other Land Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	27,491	36,871
1 - 4 Family Residential Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	5,081	7,926
Nonfarm, Nonresidential Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	10,468	16,817
Other Real Estate Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	$ 188	$ 437

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