Credit Quality of Loans and Allowance for Loan Losses - Roll Forward of Activity In Allowance for Loan Losses (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	$ 11,226	$ 8,779
Charge-offs	(2,483)	(1,678)
Recoveries	205	224
Provision	7,100	1,750
Ending balance	16,048	9,075
Ending balance: individually evaluated for impairment	2,275	563
Ending balance: collectively evaluated for impairment	13,773	8,512
Loans:
Ending balance	1,294,392	1,224,182
Ending balance: individually evaluated for impairment	44,851	6,733
Ending balance: collectively evaluated for impairment	1,248,814	1,216,644
Ending balance: loans acquired with deteriorated credit quality	727	805
Commercial, financial and agricultural
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	5,729	3,906
Charge-offs	(1,855)	(1,135)
Recoveries	144	42
Provision	5,074	1,970
Ending balance	9,092	4,783
Ending balance: individually evaluated for impairment	889	208
Ending balance: collectively evaluated for impairment	8,203	4,575
Loans:
Ending balance	471,397	454,310
Ending balance: individually evaluated for impairment	23,750	1,793
Ending balance: collectively evaluated for impairment	447,647	452,517
Ending balance: loans acquired with deteriorated credit quality	0	0
Real estate - construction
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	954	1,046
Charge-offs	(6)	0
Recoveries	0	0
Provision	20	(53)
Ending balance	968	993
Ending balance: individually evaluated for impairment	0	3
Ending balance: collectively evaluated for impairment	968	990
Loans:
Ending balance	79,176	86,238
Ending balance: individually evaluated for impairment	531	152
Ending balance: collectively evaluated for impairment	78,645	86,086
Ending balance: loans acquired with deteriorated credit quality	0	0
Real estate – commercial
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	2,402	1,389
Charge-offs	(48)	(17)
Recoveries	14	42
Provision	1,560	(23)
Ending balance	3,928	1,391
Ending balance: individually evaluated for impairment	1,123	55
Ending balance: collectively evaluated for impairment	2,805	1,336
Loans:
Ending balance	469,022	413,565
Ending balance: individually evaluated for impairment	18,423	3,234
Ending balance: collectively evaluated for impairment	449,957	409,631
Ending balance: loans acquired with deteriorated credit quality	642	700
Real estate – residential
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	810	1,141
Charge-offs	(37)	(176)
Recoveries	5	39
Provision	608	(325)
Ending balance	1,386	679
Ending balance: individually evaluated for impairment	107	152
Ending balance: collectively evaluated for impairment	1,279	527
Loans:
Ending balance	153,820	153,082
Ending balance: individually evaluated for impairment	1,823	1,214
Ending balance: collectively evaluated for impairment	151,912	151,763
Ending balance: loans acquired with deteriorated credit quality	85	105
Installment loans to individuals
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	1,311	1,273
Charge-offs	(537)	(350)
Recoveries	42	101
Provision	(173)	184
Ending balance	643	1,208
Ending balance: individually evaluated for impairment	156	145
Ending balance: collectively evaluated for impairment	487	1,063
Loans:
Ending balance	113,626	108,581
Ending balance: individually evaluated for impairment	324	340
Ending balance: collectively evaluated for impairment	113,302	108,241
Ending balance: loans acquired with deteriorated credit quality	0	0
Lease financing receivable
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	16	21
Charge-offs	0	0
Recoveries	0	0
Provision	9	(4)
Ending balance	25	17
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	25	17
Loans:
Ending balance	5,561	4,750
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	5,561	4,750
Ending balance: loans acquired with deteriorated credit quality	0	0
Other
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	4	3
Charge-offs	0	0
Recoveries	0	0
Provision	2	1
Ending balance	6	4
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	6	4
Loans:
Ending balance	1,790	3,656
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	1,790	3,656
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 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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

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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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-Name Regulation S-X (SX)

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-Section 04

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