Loans - Summary of Balances of Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Summary of balances of loans
Total loans	$ 404,852	$ 385,009
Net unamortized deferred loan costs	409	391
Allowance for loan losses	(3,993)	(3,863)
Loans, net	401,268	381,537
Construction, Land and Land Development
Summary of balances of loans
Total loans	44,119	39,818
Farmland
Summary of balances of loans
Total loans	994	1,023
Commercial Mortgages (Non-Owner Occupied)
Summary of balances of loans
Total loans	35,464	35,343
Commercial Mortgages (Owner Occupied)
Summary of balances of loans
Total loans	42,550	41,825
Residential First Mortgages
Summary of balances of loans
Total loans	205,106	194,007
Residential Revolving and Junior Mortgages
Summary of balances of loans
Total loans	27,090	26,425
Commercial and Industrial
Summary of balances of loans
Total loans	46,205	43,024
Allowance for loan losses	(528)	(493)
Consumer and Other Loans
Summary of balances of loans
Total loans	3,324	3,544
Allowance for loan losses	$ (44)	$ (52)

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 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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