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, 2015 USD ($) Contract	Dec. 31, 2014 USD ($) Contract	Dec. 31, 2013 USD ($) Contract
Troubled Debt Restructurings [Abstract]
Number of Contracts \| Contract	18		14
Pre-Modification Outstanding Recorded Investment	$ 4,301		$ 4,884
Post-Modification Outstanding Recorded Investment	$ 4,301		$ 4,820
Secured by 1-4 Family Residential Properties [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts \| Contract	13	17	10
Pre-Modification Outstanding Recorded Investment	$ 688	$ 1,248	$ 498
Post-Modification Outstanding Recorded Investment	$ 688	$ 1,234	$ 441
Loans secured by Nonfarm, Nonresidential Properties [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts \| Contract	5		1
Pre-Modification Outstanding Recorded Investment	$ 3,613		$ 952
Post-Modification Outstanding Recorded Investment	$ 3,613		$ 952
Commercial And Industrial Loans
Troubled Debt Restructurings [Abstract]
Number of Contracts \| Contract			2
Pre-Modification Outstanding Recorded Investment			$ 944
Post-Modification Outstanding Recorded Investment			$ 937
Other Loans [Member]
Troubled Debt Restructurings [Abstract]
Number of Contracts \| Contract			1
Pre-Modification Outstanding Recorded Investment			$ 2,490
Post-Modification Outstanding Recorded Investment			$ 2,490

Number of financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953676-111524

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