Credit Quality of Loans and Allowance for Loan Losses - Roll Forward of Activity In Allowance for Loan Losses (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	$ 11,226	$ 8,779
Charge-offs	(3,483)	(2,932)
Recoveries	296	653
Provision	10,900	2,925
Ending balance	18,939	9,425
Ending balance: individually evaluated for impairment	4,697	1,138
Ending balance: collectively evaluated for impairment	14,242	8,287
Loans:
Ending balance	1,301,452	1,248,373	$ 1,284,431
Ending balance: individually evaluated for impairment	51,507	7,579
Ending balance: collectively evaluated for impairment	1,249,229	1,240,018
Ending balance: loans acquired with deteriorated credit quality	716	776
Commercial, financial and agricultural
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	5,729	3,906
Charge-offs	(2,310)	(2,084)
Recoveries	185	101
Provision	8,016	2,731
Ending balance	11,620	4,654
Ending balance: individually evaluated for impairment	2,569	853
Ending balance: collectively evaluated for impairment	9,051	3,801
Loans:
Ending balance	482,452	452,065	467,147
Ending balance: individually evaluated for impairment	29,185	2,662
Ending balance: collectively evaluated for impairment	453,267	449,403
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	(76)	(1)
Recoveries	1	0
Provision	(62)	103
Ending balance	817	1,148
Ending balance: individually evaluated for impairment	26	3
Ending balance: collectively evaluated for impairment	791	1,145
Loans:
Ending balance	74,279	86,315	68,577
Ending balance: individually evaluated for impairment	212	106
Ending balance: collectively evaluated for impairment	74,067	86,209
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	(169)	(93)
Recoveries	20	398
Provision	2,107	(345)
Ending balance	4,360	1,349
Ending balance: individually evaluated for impairment	1,739	55
Ending balance: collectively evaluated for impairment	2,621	1,294
Loans:
Ending balance	473,319	430,930	467,172
Ending balance: individually evaluated for impairment	19,928	3,312
Ending balance: collectively evaluated for impairment	452,758	426,942
Ending balance: loans acquired with deteriorated credit quality	633	676
Real estate – residential
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	810	1,141
Charge-offs	(45)	(188)
Recoveries	10	44
Provision	(104)	(8)
Ending balance	671	989
Ending balance: individually evaluated for impairment	147	87
Ending balance: collectively evaluated for impairment	524	902
Loans:
Ending balance	151,667	153,915	154,602
Ending balance: individually evaluated for impairment	1,796	1,073
Ending balance: collectively evaluated for impairment	149,788	152,742
Ending balance: loans acquired with deteriorated credit quality	83	100
Installment loans to individuals
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	1,311	1,273
Charge-offs	(883)	(566)
Recoveries	80	110
Provision	923	450
Ending balance	1,431	1,267
Ending balance: individually evaluated for impairment	216	140
Ending balance: collectively evaluated for impairment	1,215	1,127
Loans:
Ending balance	113,199	116,340	119,328
Ending balance: individually evaluated for impairment	386	426
Ending balance: collectively evaluated for impairment	112,813	115,914
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	13	(6)
Ending balance	29	15
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	29	15
Loans:
Ending balance	4,790	5,285	4,857
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	4,790	5,285
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	7	0
Ending balance	11	3
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	11	3
Loans:
Ending balance	1,746	3,523	$ 2,748
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	1,746	3,523
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 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

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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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