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, 2016	Jun. 30, 2015	Dec. 31, 2015
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	$ 19,011	$ 11,226
Charge-offs	(3,019)	(2,483)
Recoveries	286	205
Provision	5,100	7,100
Ending balance	21,378	16,048
Ending balance: individually evaluated for impairment	3,803	2,275
Ending balance: collectively evaluated for impairment	17,575	13,773
Loans:
Ending balance	1,262,389	1,294,392	$ 1,263,645
Ending balance: individually evaluated for impairment	59,807	44,851
Ending balance: collectively evaluated for impairment	1,201,911	1,248,814
Ending balance: loans acquired with deteriorated credit quality	671	727
Commercial, financial and agricultural
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	11,268	5,729
Charge-offs	(2,373)	(1,855)
Recoveries	120	144
Provision	5,013	5,074
Ending balance	14,028	9,092
Ending balance: individually evaluated for impairment	1,027	889
Ending balance: collectively evaluated for impairment	13,001	8,203
Loans:
Ending balance	456,264	471,397	454,028
Ending balance: individually evaluated for impairment	29,688	23,750
Ending balance: collectively evaluated for impairment	426,576	447,647
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	(405)	20
Ending balance	414	968
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	414	968
Loans:
Ending balance	96,331	79,176	74,952
Ending balance: individually evaluated for impairment	34	531
Ending balance: collectively evaluated for impairment	96,297	78,645
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	(12)	(48)
Recoveries	84	14
Provision	162	1,560
Ending balance	4,848	3,928
Ending balance: individually evaluated for impairment	2,260	1,123
Ending balance: collectively evaluated for impairment	2,588	2,805
Loans:
Ending balance	463,142	469,022	471,141
Ending balance: individually evaluated for impairment	27,292	18,423
Ending balance: collectively evaluated for impairment	435,255	449,957
Ending balance: loans acquired with deteriorated credit quality	595	642
Real estate – residential
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	816	810
Charge-offs	(23)	(37)
Recoveries	4	5
Provision	(134)	608
Ending balance	663	1,386
Ending balance: individually evaluated for impairment	251	107
Ending balance: collectively evaluated for impairment	412	1,279
Loans:
Ending balance	148,379	153,820	149,064
Ending balance: individually evaluated for impairment	2,322	1,823
Ending balance: collectively evaluated for impairment	145,981	151,912
Ending balance: loans acquired with deteriorated credit quality	76	85
Installment loans to individuals
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	1,468	1,311
Charge-offs	(611)	(537)
Recoveries	78	42
Provision	464	(173)
Ending balance	1,399	643
Ending balance: individually evaluated for impairment	265	156
Ending balance: collectively evaluated for impairment	1,134	487
Loans:
Ending balance	94,522	113,626	111,009
Ending balance: individually evaluated for impairment	471	324
Ending balance: collectively evaluated for impairment	94,051	113,302
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)	9
Ending balance	11	25
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	11	25
Loans:
Ending balance	1,641	5,561	1,968
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	1,641	5,561
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	3	2
Ending balance	15	6
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	15	6
Loans:
Ending balance	2,110	1,790	$ 1,483
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	2,110	1,790
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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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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