Risk Category of Loans by Class of Loans (Excluding Mortgage Loans Held for Sale) (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 731,443	$ 704,971
Less: Unearned discount	406	440
Loans, net of unearned discount	731,037	704,531
Pass
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	706,651	682,079
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	4,800	5,445
Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	19,992	17,447
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	0	0
Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	424,965	408,051
Less: Unearned discount	301	320
Loans, net of unearned discount	424,664	407,731
Commercial Real Estate \| Pass
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	403,194	388,568
Commercial Real Estate \| Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	4,443	4,756
Commercial Real Estate \| Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	17,328	14,727
Commercial Real Estate \| Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	0	0
Mortgage Real Estate
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	171,247	170,585
Less: Unearned discount	78	82
Loans, net of unearned discount	171,169	170,503
Mortgage Real Estate \| Pass
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	169,139	167,827
Mortgage Real Estate \| Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	187	191
Mortgage Real Estate \| Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	1,921	2,567
Mortgage Real Estate \| Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	0	0
Installment and Other
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	19,875	18,648
Less: Unearned discount	0	0
Loans, net of unearned discount	19,875	18,648
Installment and Other \| Pass
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	19,791	18,558
Installment and Other \| Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	0	0
Installment and Other \| Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	84	90
Installment and Other \| Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	0	0
Commercial,Financial and Agricultural
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	115,356	107,687
Less: Unearned discount	27	38
Loans, net of unearned discount	115,329	107,649
Commercial,Financial and Agricultural \| Pass
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	114,527	107,126
Commercial,Financial and Agricultural \| Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	170	498
Commercial,Financial and Agricultural \| Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	659	63
Commercial,Financial and Agricultural \| Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans and leases receivable, gross	$ 0	$ 0

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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