LHFI and Allowance for Loan Losses, LHFI - Impact of Modifications Classified as Troubled Debt Restructurings (Details) - Troubled Debt Restructurings [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) Contract	Dec. 31, 2015 USD ($) Contract	Dec. 31, 2014 USD ($) Contract
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	27	18
Pre-Modification Outstanding Recorded Investment	$ 12,162	$ 4,301
Post-Modification Outstanding Recorded Investment	$ 12,106	$ 4,301
Construction, Land Development and Other Land Loans [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	1
Pre-Modification Outstanding Recorded Investment	$ 14
Post-Modification Outstanding Recorded Investment	$ 14
Secured by Nonfarm, Nonresidential Properties [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	2	5
Pre-Modification Outstanding Recorded Investment	$ 717	$ 3,613
Post-Modification Outstanding Recorded Investment	$ 717	$ 3,613
Consumer Loans [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	1
Pre-Modification Outstanding Recorded Investment	$ 2
Post-Modification Outstanding Recorded Investment	$ 2
Secured by 1-4 Family Residential Properties [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	18	13	17
Pre-Modification Outstanding Recorded Investment	$ 1,386	$ 688	$ 1,248
Post-Modification Outstanding Recorded Investment	$ 1,391	$ 688	$ 1,234
Commercial And Industrial
Troubled Debt Restructurings [Abstract]
Number of Contracts | Contract	5
Pre-Modification Outstanding Recorded Investment	$ 10,043
Post-Modification Outstanding Recorded Investment	$ 9,982