Loans - Loan Balances (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 1,573,193	$ 1,561,941
Allowance for loan losses	(13,822)	(13,679)
Net loans	1,559,371	1,548,262
Commercial and Agriculture [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	179,200	177,101
Commercial Real Estate Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	217,030	210,121
Commercial Real Estate Non Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	539,420	523,598
Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	461,340	457,850
Real Estate Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	123,905	135,195
Farm Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	35,645	38,513
Consumer and Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans	$ 16,653	$ 19,563

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.

No definition available.

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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.

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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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