Loans - Roll Forward of Activity In Allowance for Loan Losses (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	$ 24,372	$ 19,011
Charge-offs	(15,565)	(3,019)
Recoveries	567	286
Provision	15,300	5,100
Ending balance	24,674	21,378
Ending balance: individually evaluated for impairment	4,352	3,803
Ending balance: collectively evaluated for impairment	20,322	17,575
Loans:
Ending balance	1,240,253	1,262,389	$ 1,284,082
Ending balance: individually evaluated for impairment	56,463	59,807
Ending balance: collectively evaluated for impairment	1,183,294	1,201,911
Ending balance: loans acquired with deteriorated credit quality	496	671
Commercial, financial and agricultural
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	16,057	11,268
Charge-offs	(11,319)	(2,373)
Recoveries	290	120
Provision	13,272	5,013
Ending balance	18,300	14,028
Ending balance: individually evaluated for impairment	3,092	1,027
Ending balance: collectively evaluated for impairment	15,208	13,001
Loans:
Ending balance	451,767	456,264	459,574
Ending balance: individually evaluated for impairment	35,276	29,688
Ending balance: collectively evaluated for impairment	416,491	426,576
Ending balance: loans acquired with deteriorated credit quality	0	0
Real estate - construction
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	585	819
Charge-offs	(1)	0
Recoveries	0	0
Provision	623	(405)
Ending balance	1,207	414
Ending balance: individually evaluated for impairment	9	0
Ending balance: collectively evaluated for impairment	1,198	414
Loans:
Ending balance	98,695	96,331	100,959
Ending balance: individually evaluated for impairment	25	34
Ending balance: collectively evaluated for impairment	98,670	96,297
Ending balance: loans acquired with deteriorated credit quality	0	0
Real estate – commercial
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	5,384	4,614
Charge-offs	(3,448)	(12)
Recoveries	33	84
Provision	1,845	162
Ending balance	3,814	4,848
Ending balance: individually evaluated for impairment	1,120	2,260
Ending balance: collectively evaluated for impairment	2,694	2,588
Loans:
Ending balance	461,064	463,142	481,155
Ending balance: individually evaluated for impairment	19,526	27,292
Ending balance: collectively evaluated for impairment	441,108	435,255
Ending balance: loans acquired with deteriorated credit quality	430	595
Real estate – residential
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	940	816
Charge-offs	(198)	(23)
Recoveries	96	4
Provision	(438)	(134)
Ending balance	400	663
Ending balance: individually evaluated for impairment	28	251
Ending balance: collectively evaluated for impairment	372	412
Loans:
Ending balance	156,394	148,379	157,872
Ending balance: individually evaluated for impairment	1,325	2,322
Ending balance: collectively evaluated for impairment	155,003	145,981
Ending balance: loans acquired with deteriorated credit quality	66	76
Installment loans to individuals
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	1,395	1,468
Charge-offs	(599)	(611)
Recoveries	148	78
Provision	(1)	464
Ending balance	943	1,399
Ending balance: individually evaluated for impairment	103	265
Ending balance: collectively evaluated for impairment	840	1,134
Loans:
Ending balance	70,031	94,522	82,660
Ending balance: individually evaluated for impairment	311	471
Ending balance: collectively evaluated for impairment	69,720	94,051
Ending balance: loans acquired with deteriorated credit quality	0	0
Lease financing receivable
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	5	14
Charge-offs	0	0
Recoveries	0	0
Provision	(2)	(3)
Ending balance	3	11
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	3	11
Loans:
Ending balance	866	1,641	1,095
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	866	1,641
Ending balance: loans acquired with deteriorated credit quality	0	0
Other
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	6	12
Charge-offs	0	0
Recoveries	0	0
Provision	1	3
Ending balance	7	15
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	7	15
Loans:
Ending balance	1,436	2,110	$ 767
Ending balance: individually evaluated for impairment	0	0
Ending balance: collectively evaluated for impairment	1,436	2,110
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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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=65884687&loc=d3e4428-111522

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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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