Loans - Roll Forward of Activity In Allowance for Loan Losses (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	$ 26,888	$ 24,372
Charge-offs	(8,977)	(19,947)
Recoveries	1,799	1,027
Provision	4,740	19,601
Ending balance	24,450	25,053
Ending balance: individually evaluated for impairment	7,547	4,252
Ending balance: collectively evaluated for impairment	16,903	20,801
Loans:
Ending balance	962,743	1,235,969	$ 1,183,426
Ending balance: individually evaluated for impairment	48,708	52,843
Ending balance: collectively evaluated for impairment	914,035	1,182,637
Ending balance: loans acquired with deteriorated credit quality		489
Commercial, financial and agricultural
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	20,577	16,057
Charge-offs	(6,782)	(15,106)
Recoveries	1,628	537
Provision	2,872	17,413
Ending balance	18,295	18,901
Ending balance: individually evaluated for impairment	7,373	3,254
Ending balance: collectively evaluated for impairment	10,922	15,647
Loans:
Ending balance	295,802	447,482	435,207
Ending balance: individually evaluated for impairment	24,923	30,892
Ending balance: collectively evaluated for impairment	270,879	416,590
Ending balance: loans acquired with deteriorated credit quality		0
Real estate – construction
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	596	585
Charge-offs	(6)	(70)
Recoveries	0	0
Provision	(240)	28
Ending balance	350	543
Ending balance: individually evaluated for impairment	69	17
Ending balance: collectively evaluated for impairment	281	526
Loans:
Ending balance	90,444	90,088	90,287
Ending balance: individually evaluated for impairment	610	2,416
Ending balance: collectively evaluated for impairment	89,834	87,672
Ending balance: loans acquired with deteriorated credit quality		0
Real estate – commercial
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	3,893	5,384
Charge-offs	(1,034)	(3,618)
Recoveries	7	158
Provision	687	2,024
Ending balance	3,553	3,948
Ending balance: individually evaluated for impairment	105	904
Ending balance: collectively evaluated for impairment	3,448	3,044
Loans:
Ending balance	394,416	473,046	454,051
Ending balance: individually evaluated for impairment	23,175	18,132
Ending balance: collectively evaluated for impairment	371,241	454,488
Ending balance: loans acquired with deteriorated credit quality		426
Real estate – residential
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	837	940
Charge-offs	(549)	(293)
Recoveries	1	97
Provision	1,094	(40)
Ending balance	1,383	704
Ending balance: individually evaluated for impairment	0	7
Ending balance: collectively evaluated for impairment	1,383	697
Loans:
Ending balance	136,151	155,676	146,751
Ending balance: individually evaluated for impairment	0	1,031
Ending balance: collectively evaluated for impairment	136,151	154,582
Ending balance: loans acquired with deteriorated credit quality		63
Consumer and other
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	982	1,401
Charge-offs	(606)	(860)
Recoveries	163	235
Provision	327	177
Ending balance	866	953
Ending balance: individually evaluated for impairment	0	69
Ending balance: collectively evaluated for impairment	866	884
Loans:
Ending balance	45,338	68,917	56,398
Ending balance: individually evaluated for impairment	0	338
Ending balance: collectively evaluated for impairment	45,338	68,579
Ending balance: loans acquired with deteriorated credit quality		0
Lease financing receivable
Allowance for loan losses by portfolio [Roll Forward]
Beginning balance	3	5
Charge-offs	0	0
Recoveries	0	0
Provision	0	(1)
Ending balance	3	4
Ending balance: individually evaluated for impairment	0	1
Ending balance: collectively evaluated for impairment	3	3
Loans:
Ending balance	592	760	$ 732
Ending balance: individually evaluated for impairment	0	34
Ending balance: collectively evaluated for impairment	$ 592	726
Ending balance: loans acquired with deteriorated credit quality		$ 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.

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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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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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