Allowance for Loan Losses - Activity in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 32,423	$ 27,122
Provision for Loan Losses	1,397	1,085
Charge- Offs	(1,479)	(505)
Recoveries	516	504
TDR Allowance Adjustments	(35)	(88)
Ending Balance	32,822	28,118
Construction and land development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	2,233	1,642
Provision for Loan Losses	83	411
Charge- Offs	0	0
Recoveries	4	5
TDR Allowance Adjustments	0	0
Ending Balance	2,320	2,058
Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	11,112	9,285
Provision for Loan Losses	625	(575)
Charge- Offs	(16)	0
Recoveries	47	147
TDR Allowance Adjustments	(15)	(15)
Ending Balance	11,753	8,842
Residential real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	7,775	7,131
Provision for Loan Losses	(414)	788
Charge- Offs	(36)	0
Recoveries	139	200
TDR Allowance Adjustments	(19)	(72)
Ending Balance	7,445	8,047
Commercial and financial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	8,585	7,297
Provision for Loan Losses	853	270
Charge- Offs	(944)	(198)
Recoveries	79	24
TDR Allowance Adjustments	0	0
Ending Balance	8,573	7,393
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	2,718	1,767
Provision for Loan Losses	250	191
Charge- Offs	(483)	(307)
Recoveries	247	128
TDR Allowance Adjustments	(1)	(1)
Ending Balance	$ 2,731	$ 1,778

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
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-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
-SubTopic 10
-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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-SubTopic 30
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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- Definition

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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