Other Real Estate and Covered Other Real Estate - Other Real Estate, Excluding Covered Other Real Estate, By Type of Property (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
Other real estate, excluding covered other real estate [Line Items]
Other real estate, excluding covered other real estate	$ 64,993	$ 77,177	$ 83,955	$ 92,509
Construction, Land Development And Other Land Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Other real estate, excluding covered other real estate	38,345	47,550
1 - 4 Family Residential Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Other real estate, excluding covered other real estate	8,037	10,732
Nonfarm, Nonresidential Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Other real estate, excluding covered other real estate	$ 18,611	16,717
Other Real Estate Properties [Member]
Other real estate, excluding covered other real estate [Line Items]
Other real estate, excluding covered other real estate		$ 2,178