Allowance for Loan Losses - Activity in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 28,924	$ 26,000	$ 27,122	$ 23,400
Provision for Loan Losses	5,774	680	9,388	3,385
Charge- Offs	(1,145)	(1,310)	(3,964)	(2,416)
Recoveries	348	1,031	1,476	2,145
TDR Allowance Adjustments	(36)	(169)	(157)	(282)
Ending Balance	33,865	26,232	33,865	26,232
Real Estate \| Construction and land development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	2,287	1,574	1,642	1,219
Provision for Loan Losses	(221)	(690)	414	(496)
Charge- Offs	0	0	0	0
Recoveries	3	728	13	891
TDR Allowance Adjustments	0	0	0	(2)
Ending Balance	2,069	1,612	2,069	1,612
Real Estate \| Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	9,126	9,923	9,285	9,273
Provision for Loan Losses	4,191	62	3,826	410
Charge- Offs	(1)	(239)	(15)	(341)
Recoveries	18	175	268	613
TDR Allowance Adjustments	(16)	(15)	(46)	(49)
Ending Balance	13,318	9,906	13,318	9,906
Real Estate \| Residential real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	8,850	7,423	7,131	7,483
Provision for Loan Losses	(1,279)	116	(78)	90
Charge- Offs	(6)	(296)	(33)	(482)
Recoveries	99	39	733	266
TDR Allowance Adjustments	(19)	(148)	(108)	(223)
Ending Balance	7,645	7,134	7,645	7,134
Commercial and financial \| Commercial and financial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	7,102	5,460	7,297	3,636
Provision for Loan Losses	1,739	834	3,639	3,036
Charge- Offs	(842)	(333)	(2,985)	(837)
Recoveries	163	28	211	154
TDR Allowance Adjustments	0	0	0	0
Ending Balance	8,162	5,989	8,162	5,989
Consumer \| Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	1,559	1,620	1,767	1,789
Provision for Loan Losses	1,344	358	1,587	345
Charge- Offs	(296)	(442)	(931)	(756)
Recoveries	65	61	251	221
TDR Allowance Adjustments	(1)	(6)	(3)	(8)
Ending Balance	$ 2,671	$ 1,591	$ 2,671	$ 1,591

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

Amount of other addition (reduction) in allowance reserve for credit loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for 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 50
-Paragraph 11B
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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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.

+ References

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