Loans - Summary of Balances of Loans (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Summary of balances of loans
Total loans	$ 298,054	$ 250,331
Net unamortized deferred loans costs	393	506
Allowance for loan losses	(3,205)	(2,925)
Loans, net	295,242	247,912
Construction, Land and Land Development
Summary of balances of loans
Total loans	43,048	31,839
Farmland
Summary of balances of loans
Total loans	1,128	1,262
Commercial Mortgages (Non-Owner Occupied)
Summary of balances of loans
Total loans	20,534	14,626
Commercial Mortgages (Owner Occupied)
Summary of balances of loans
Total loans	33,326	34,177
Residential First Mortgages
Summary of balances of loans
Total loans	135,267	114,458
Residential Revolving and Junior Mortgages
Summary of balances of loans
Total loans	25,400	24,045
Commercial and Industrial loans
Summary of balances of loans
Total loans	34,002	23,938
Consumer Loans
Summary of balances of loans
Total loans	$ 5,349	$ 5,986

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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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 after allowance and 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 and loans held for sale.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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