Loans Modified as Troubled Debt Restructurings by Type of Concession Made and Loan Class (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014 Contract
Financing Receivable, Modifications [Line Items]
Total Contracts	5
Pre-Modification Recorded Investment	$ 948
Post-Modification Recorded Investment	948
Below Market Interest Rate
Financing Receivable, Modifications [Line Items]
Total Contracts	1
Pre-Modification Recorded Investment	245
Post-Modification Recorded Investment	245
Below Market Interest Rate \| Owner Occupied Construction
Financing Receivable, Modifications [Line Items]
Total Contracts	1
Pre-Modification Recorded Investment	245
Post-Modification Recorded Investment	245
Extended Payment Term
Financing Receivable, Modifications [Line Items]
Total Contracts	2
Pre-Modification Recorded Investment	437
Post-Modification Recorded Investment	437
Extended Payment Term \| Single-family Non-owner Occupied
Financing Receivable, Modifications [Line Items]
Total Contracts	1
Pre-Modification Recorded Investment	303
Post-Modification Recorded Investment	303
Extended Payment Term \| Non-farm, Non-residential
Financing Receivable, Modifications [Line Items]
Total Contracts	1
Pre-Modification Recorded Investment	134
Post-Modification Recorded Investment	134
Below Market Interest Rate And Extended Payment Term \| Single-family Non-owner Occupied
Financing Receivable, Modifications [Line Items]
Total Contracts	2
Pre-Modification Recorded Investment	266
Post-Modification Recorded Investment	$ 266

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

+ References

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=35738203&loc=SL6953676-111524

+ Details

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

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