Allowance for Loan Losses - Schedule of Troubled Debt Restructurings (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2015 USD ($) Contract	Jun. 30, 2014 USD ($) Contract
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Contracts \| Contract	5	2
Pre-Modification Outstanding Recorded Investment	$ 421	$ 149
Post-Modification Outstanding Recorded Investment	$ 421	$ 149
Commercial and Agriculture [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Contracts \| Contract	1
Pre-Modification Outstanding Recorded Investment	$ 6
Post-Modification Outstanding Recorded Investment	$ 6
Residential Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Contracts \| Contract	3	2
Pre-Modification Outstanding Recorded Investment	$ 374	$ 149
Post-Modification Outstanding Recorded Investment	$ 374	$ 149
Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of Contracts \| Contract	1
Pre-Modification Outstanding Recorded Investment	$ 41
Post-Modification Outstanding Recorded Investment	$ 41

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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