Loans and Allowance for Loan Losses - Schedule of Average Net Investment Impaired Loans and Interest Income Recognized and Received on Impaired Loans (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Financing Receivable Impaired [Line Items]
Average Recorded Investment	$ 17,562	$ 14,743
Interest Income Recognized	395	552
Interest Income Received	377	540
Real Estate [Member] \| Construction, Land Development and Other Land Loans [Member]
Financing Receivable Impaired [Line Items]
Average Recorded Investment	3,081	2,769
Interest Income Recognized	20	46
Interest Income Received	22	46
Real Estate [Member] \| Secured by 1-4 Family Residential Properties [Member]
Financing Receivable Impaired [Line Items]
Average Recorded Investment	193	143
Interest Income Recognized		3
Interest Income Received		3
Real Estate [Member] \| Secured by Multi-family Residential Properties [Member]
Financing Receivable Impaired [Line Items]
Average Recorded Investment	4,997	3,565
Interest Income Recognized	72	178
Interest Income Received	63	170
Real Estate [Member] \| Secured by Non-farm, Non-residential Properties [Member]
Financing Receivable Impaired [Line Items]
Average Recorded Investment	9,138	8,186
Interest Income Recognized	289	324
Interest Income Received	279	320
Commercial and Industrial Loans [Member]
Financing Receivable Impaired [Line Items]
Average Recorded Investment	153	80
Interest Income Recognized	14	1
Interest Income Received	$ 13	$ 1

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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