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, 2016	Sep. 30, 2015	Dec. 31, 2015
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	$ 19,011	$ 11,226
Charge-offs	(4,180)	(3,483)
Recoveries	437	296
Provision	8,000	10,900
Ending balance	23,268	18,939
Ending balance: individually evaluated for impairment	3,837	4,697
Ending balance: collectively evaluated for impairment	19,431	14,242
Loans:
Ending balance	1,272,800	1,301,452	$ 1,263,645
Ending balance: individually evaluated for impairment	60,477	51,507
Ending balance: collectively evaluated for impairment	1,211,665	1,249,229
Ending balance: loans acquired with deteriorated credit quality	658	716
Commercial, financial and agricultural
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	11,268	5,729
Charge-offs	(2,957)	(2,310)
Recoveries	193	185
Provision	6,747	8,016
Ending balance	15,251	11,620
Ending balance: individually evaluated for impairment	1,105	2,569
Ending balance: collectively evaluated for impairment	14,146	9,051
Loans:
Ending balance	463,031	482,452	454,028
Ending balance: individually evaluated for impairment	29,887	29,185
Ending balance: collectively evaluated for impairment	433,144	453,267
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	(76)
Recoveries	0	1
Provision	(478)	(62)
Ending balance	341	817
Ending balance: individually evaluated for impairment	0	26
Ending balance: collectively evaluated for impairment	341	791
Loans:
Ending balance	96,365	74,279	74,952
Ending balance: individually evaluated for impairment	10	212
Ending balance: collectively evaluated for impairment	96,355	74,067
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	(208)	(169)
Recoveries	115	20
Provision	1,042	2,107
Ending balance	5,563	4,360
Ending balance: individually evaluated for impairment	2,270	1,739
Ending balance: collectively evaluated for impairment	3,293	2,621
Loans:
Ending balance	464,853	473,319	471,141
Ending balance: individually evaluated for impairment	28,285	19,928
Ending balance: collectively evaluated for impairment	435,985	452,758
Ending balance: loans acquired with deteriorated credit quality	583	633
Real estate – residential
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	816	810
Charge-offs	(24)	(45)
Recoveries	4	10
Provision	(97)	(104)
Ending balance	699	671
Ending balance: individually evaluated for impairment	194	147
Ending balance: collectively evaluated for impairment	505	524
Loans:
Ending balance	155,653	151,667	149,064
Ending balance: individually evaluated for impairment	1,831	1,796
Ending balance: collectively evaluated for impairment	153,747	149,788
Ending balance: loans acquired with deteriorated credit quality	75	83
Installment loans to individuals
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	1,468	1,311
Charge-offs	(991)	(883)
Recoveries	125	80
Provision	781	923
Ending balance	1,383	1,431
Ending balance: individually evaluated for impairment	268	216
Ending balance: collectively evaluated for impairment	1,115	1,215
Loans:
Ending balance	88,537	113,199	111,009
Ending balance: individually evaluated for impairment	464	386
Ending balance: collectively evaluated for impairment	88,073	112,813
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	(5)	13
Ending balance	9	29
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	9	29
Loans:
Ending balance	1,449	4,790	1,968
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	1,449	4,790
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	10	7
Ending balance	22	11
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	22	11
Loans:
Ending balance	2,912	1,746	$ 1,483
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	2,912	1,746
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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