Credit Quality of Loans and Allowance for Loan Losses - Roll Forward of Activity In Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	$ 19,011	$ 11,226
Charge-offs	(1,594)	(1,332)
Recoveries	130	166
Provision	2,800	6,000
Ending balance	20,347	16,060
Ending balance: individually evaluated for impairment	4,152	1,645
Ending balance: collectively evaluated for impairment	16,195	14,415
Loans:
Ending balance	1,250,049	1,310,929	$ 1,263,645
Ending balance: individually evaluated for impairment	59,379	12,757
Ending balance: collectively evaluated for impairment	1,189,985	1,297,429
Ending balance: loans acquired with deteriorated credit quality	685	743
Commercial, financial and agricultural
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	11,268	5,729
Charge-offs	(1,307)	(1,001)
Recoveries	26	132
Provision	2,194	5,523
Ending balance	12,181	10,383
Ending balance: individually evaluated for impairment	1,021	737
Ending balance: collectively evaluated for impairment	11,160	9,646
Loans:
Ending balance	441,160	484,508	454,028
Ending balance: individually evaluated for impairment	29,097	2,427
Ending balance: collectively evaluated for impairment	412,063	482,081
Ending balance: loans acquired with deteriorated credit quality	0	0
Real estate - construction
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	819	954
Charge-offs	0	(6)
Recoveries	0	0
Provision	(420)	3
Ending balance	399	951
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	399	951
Loans:
Ending balance	84,790	76,964	74,952
Ending balance: individually evaluated for impairment	35	477
Ending balance: collectively evaluated for impairment	84,755	76,487
Ending balance: loans acquired with deteriorated credit quality	0	0
Real estate – commercial
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	4,614	2,402
Charge-offs	0	0
Recoveries	76	6
Provision	861	202
Ending balance	5,551	2,610
Ending balance: individually evaluated for impairment	2,586	645
Ending balance: collectively evaluated for impairment	2,965	1,965
Loans:
Ending balance	467,648	471,737	471,141
Ending balance: individually evaluated for impairment	27,511	7,977
Ending balance: collectively evaluated for impairment	439,530	463,106
Ending balance: loans acquired with deteriorated credit quality	607	654
Real estate – residential
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	816	810
Charge-offs	(4)	(2)
Recoveries	3	2
Provision	(170)	7
Ending balance	645	817
Ending balance: individually evaluated for impairment	267	57
Ending balance: collectively evaluated for impairment	378	760
Loans:
Ending balance	149,961	153,647	149,064
Ending balance: individually evaluated for impairment	2,230	1,471
Ending balance: collectively evaluated for impairment	147,653	152,087
Ending balance: loans acquired with deteriorated credit quality	78	89
Installment loans to individuals
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	1,468	1,311
Charge-offs	(283)	(323)
Recoveries	25	26
Provision	336	260
Ending balance	1,546	1,274
Ending balance: individually evaluated for impairment	278	206
Ending balance: collectively evaluated for impairment	1,268	1,068
Loans:
Ending balance	103,181	115,284	111,009
Ending balance: individually evaluated for impairment	506	405
Ending balance: collectively evaluated for impairment	102,675	114,879
Ending balance: loans acquired with deteriorated credit quality	0	0
Lease financing receivable
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	14	16
Charge-offs	0	0
Recoveries	0	0
Provision	(3)	4
Ending balance	11	20
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	11	20
Loans:
Ending balance	1,590	6,350	1,968
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	1,590	6,350
Ending balance: loans acquired with deteriorated credit quality	0	0
Other
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	12	4
Charge-offs	0	0
Recoveries	0	0
Provision	2	1
Ending balance	14	5
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	14	5
Loans:
Ending balance	1,719	2,439	$ 1,483
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	1,719	2,439
Ending balance: loans acquired with deteriorated credit quality	$ 0	$ 0

The balance of financing receivables that were acquired with deteriorated credit quality.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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

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Amount of direct write-downs of financing receivables charged against the allowance.

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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=28367877&loc=d3e4428-111522

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5074-111524

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 11
-Article 9

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