Loans - Summary of Loan Portfolio (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Loan portfolio [Abstract]
Ending balance	$ 1,272,000	$ 1,284,082	$ 1,250,049
Less allowance for loan losses	(24,578)	(24,372)
Loans, net	1,247,422	1,259,710
Commercial, financial and agricultural
Loan portfolio [Abstract]
Ending balance	469,815	459,574	441,160
Real estate - construction
Loan portfolio [Abstract]
Ending balance	100,248	100,959	84,790
Real estate – commercial
Loan portfolio [Abstract]
Ending balance	464,859	481,155	467,648
Real estate – residential
Loan portfolio [Abstract]
Ending balance	159,426	157,872	149,961
Installment loans to individuals
Loan portfolio [Abstract]
Ending balance	75,258	82,660	103,181
Lease financing receivable
Loan portfolio [Abstract]
Ending balance	969	1,095	1,590
Other
Loan portfolio [Abstract]
Ending balance	$ 1,425	$ 767	$ 1,719

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

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