Other Real Estate - Other Real Estate, By Type of Property (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
Construction, Land Development And Other Land Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	18,976	27,491
1 - 4 Family Residential Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	5,266	5,081
Nonfarm, Nonresidential Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	12,050	10,468
Other Real Estate Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Total other real estate	$ 183	$ 188