Amount before allowance of loans and leases held in portfolio. Excludes deferred income.

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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 of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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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 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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Loans - Summary of loans (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 1,036,812		$ 1,009,315
Less allowance for loan losses	21,368	$ 21,401	21,367	$ 22,180	$ 23,372	$ 25,506
Less deferred loan origination fees (costs)	21		166
Loans, net	1,015,423		987,782
Commercial, financial, and agricultural
Loans and Leases Receivable Disclosure [Line Items]
Loans	216,316		210,712
Less allowance for loan losses	4,649	5,589	4,908	4,428	4,427	5,407
Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Loans	381,882		366,566
Residential real estate
Loans and Leases Receivable Disclosure [Line Items]
Loans	250,111		229,161
Less allowance for loan losses	5,365	5,107	5,027	6,861	6,336	6,591
Acquisition, development and construction real estate
Loans and Leases Receivable Disclosure [Line Items]
Loans	168,396		184,292
Consumer installment
Loans and Leases Receivable Disclosure [Line Items]
Loans	20,107		18,584
Less allowance for loan losses	$ 683	$ 667	$ 673	$ 627	$ 601	$ 623