Loans - Loan Balances (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 1,046,967	$ 1,001,527
Allowance for loan losses	(13,451)	(14,361)
Net loans	1,033,516	987,166
Commercial and Agriculture [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	129,700	124,402
Commercial Real Estate Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	167,564	167,897
Commercial Real Estate Non Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	385,863	348,439
Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	247,174	236,338
Real Estate Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	56,919	58,898
Farm Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	41,862	46,993
Consumer and Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 17,885	$ 18,560

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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.

+ References

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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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