Credit Quality of Loans and Allowance for Loan Losses - Summary of Loan Portfolio (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Loan portfolio [Abstract]
Ending balance	$ 1,235,969	$ 1,284,082	$ 1,272,800
Less allowance for loan losses	(25,053)	(24,372)
Loans, net	1,210,916	1,259,710
Commercial, financial and agricultural
Loan portfolio [Abstract]
Ending balance	447,482	459,574	463,031
Real estate - construction
Loan portfolio [Abstract]
Ending balance	90,088	100,959	96,365
Real estate – commercial
Receivables [Abstract]
Total CRE loans on non-accrual	20,500
Loan portfolio [Abstract]
Ending balance	473,046	481,155	464,853
Real estate – residential
Loan portfolio [Abstract]
Ending balance	155,676	157,872	155,653
Installment loans to individuals
Loan portfolio [Abstract]
Ending balance	63,148	82,660	88,537
Lease financing receivable
Loan portfolio [Abstract]
Ending balance	760	1,095	1,449
Other
Loan portfolio [Abstract]
Ending balance	$ 5,769	$ 767	$ 2,912

Total CRE loans on non-accrual

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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 and after 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.

+ References

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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.

+ References

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