Loans - Summary of Balances of Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Summary of balances of loans
Total loans	$ 385,009	$ 347,222
Net unamortized deferred loan costs	391	324
Allowance for loan losses	(3,863)	(4,223)
Loans, net	381,537	343,323
Construction, Land and Land Development
Summary of balances of loans
Total loans	39,818	42,129
Farmland
Summary of balances of loans
Total loans	1,023	1,030
Commercial Mortgages (Non-Owner Occupied)
Summary of balances of loans
Total loans	35,343	29,086
Commercial Mortgages (Owner Occupied)
Summary of balances of loans
Total loans	41,825	43,956
Residential First Mortgages
Summary of balances of loans
Total loans	194,007	164,405
Residential Revolving and Junior Mortgages
Summary of balances of loans
Total loans	26,425	26,497
Commercial and Industrial
Summary of balances of loans
Total loans	43,024	35,104
Consumer and Other Loans
Summary of balances of loans
Total loans	$ 3,544	$ 5,015

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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