Loans - Roll Forward of Activity In Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	$ 24,372	$ 19,011
Charge-offs	(2,906)	(1,594)
Recoveries	312	130
Provision	2,800	2,800
Ending balance	24,578	20,347
Ending balance: individually evaluated for impairment	6,215	4,152
Ending balance: collectively evaluated for impairment	18,363	16,195
Loans:
Ending balance	1,272,000	1,250,049	$ 1,284,082
Ending balance: individually evaluated for impairment	58,438	59,379
Ending balance: collectively evaluated for impairment	1,213,059	1,189,985
Ending balance: loans acquired with deteriorated credit quality	503	685
Commercial, financial and agricultural
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	16,057	11,268
Charge-offs	(1,705)	(1,307)
Recoveries	154	26
Provision	3,832	2,194
Ending balance	18,338	12,181
Ending balance: individually evaluated for impairment	4,173	1,021
Ending balance: collectively evaluated for impairment	14,165	11,160
Loans:
Ending balance	469,815	441,160	459,574
Ending balance: individually evaluated for impairment	35,346	29,097
Ending balance: collectively evaluated for impairment	434,469	412,063
Ending balance: loans acquired with deteriorated credit quality	0	0
Real estate - construction
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	585	819
Charge-offs	0	0
Recoveries	0	0
Provision	(321)	(420)
Ending balance	264	399
Ending balance: individually evaluated for impairment	9	0
Ending balance: collectively evaluated for impairment	255	399
Loans:
Ending balance	100,248	84,790	100,959
Ending balance: individually evaluated for impairment	26	35
Ending balance: collectively evaluated for impairment	100,222	84,755
Ending balance: loans acquired with deteriorated credit quality	0	0
Real estate – commercial
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	5,384	4,614
Charge-offs	(823)	0
Recoveries	10	76
Provision	(238)	861
Ending balance	4,333	5,551
Ending balance: individually evaluated for impairment	1,656	2,586
Ending balance: collectively evaluated for impairment	2,677	2,965
Loans:
Ending balance	464,859	467,648	481,155
Ending balance: individually evaluated for impairment	20,623	27,511
Ending balance: collectively evaluated for impairment	443,802	439,530
Ending balance: loans acquired with deteriorated credit quality	434	607
Real estate – residential
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	940	816
Charge-offs	(117)	(4)
Recoveries	90	3
Provision	(249)	(170)
Ending balance	664	645
Ending balance: individually evaluated for impairment	217	267
Ending balance: collectively evaluated for impairment	447	378
Loans:
Ending balance	159,426	149,961	157,872
Ending balance: individually evaluated for impairment	1,956	2,230
Ending balance: collectively evaluated for impairment	157,401	147,653
Ending balance: loans acquired with deteriorated credit quality	69	78
Installment loans to individuals
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	1,395	1,468
Charge-offs	(261)	(283)
Recoveries	58	25
Provision	(222)	336
Ending balance	970	1,546
Ending balance: individually evaluated for impairment	160	278
Ending balance: collectively evaluated for impairment	810	1,268
Loans:
Ending balance	75,258	103,181	82,660
Ending balance: individually evaluated for impairment	487	506
Ending balance: collectively evaluated for impairment	74,771	102,675
Ending balance: loans acquired with deteriorated credit quality	0	0
Lease financing receivable
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	5	14
Charge-offs	0	0
Recoveries	0	0
Provision	(2)	(3)
Ending balance	3	11
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	3	11
Loans:
Ending balance	969	1,590	1,095
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	969	1,590
Ending balance: loans acquired with deteriorated credit quality	0	0
Other
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	6	12
Charge-offs	0	0
Recoveries	0	0
Provision	0	2
Ending balance	6	14
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	6	14
Loans:
Ending balance	1,425	1,719	$ 767
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	1,425	1,719
Ending balance: loans acquired with deteriorated credit quality	$ 0	$ 0

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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A valuation allowance for financing receivables that are expected to be uncollectible.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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