Allowance for Loan Losses - Activity in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for Loan Losses:
Beginning Balance	$ 27,122	$ 23,400	$ 19,128
Provision for loan losses	11,730	5,648	2,411
Charge- Offs	(8,026)	(4,102)	(1,144)
Recoveries	1,789	2,495	3,236
TDR Allowance Adjustments	(192)	(319)	(231)
Ending Balance	32,423	27,122	23,400
Real Estate \| Construction and land development
Allowance for Loan Losses:
Beginning Balance	1,642	1,219	1,151
Provision for loan losses	564	(471)	(150)
Charge- Offs	0	0	0
Recoveries	27	896	226
TDR Allowance Adjustments	0	(2)	(8)
Ending Balance	2,233	1,642	1,219
Real Estate \| Commercial real estate
Allowance for Loan Losses:
Beginning Balance	9,285	9,273	6,756
Provision for loan losses	4,736	(264)	2,599
Charge- Offs	(3,139)	(407)	(256)
Recoveries	292	747	306
TDR Allowance Adjustments	(62)	(64)	(132)
Ending Balance	11,112	9,285	9,273
Real Estate \| Residential real estate
Allowance for Loan Losses:
Beginning Balance	7,131	7,483	8,057
Provision for loan losses	29	125	(1,069)
Charge- Offs	(80)	(569)	(205)
Recoveries	816	336	786
TDR Allowance Adjustments	(121)	(244)	(86)
Ending Balance	7,775	7,131	7,483
Commercial and financial \| Commercial and financial
Allowance for Loan Losses:
Beginning Balance	7,297	3,636	2,042
Provision for loan losses	4,359	5,304	224
Charge- Offs	(3,396)	(1,869)	(439)
Recoveries	325	226	1,809
TDR Allowance Adjustments	0	0	0
Ending Balance	8,585	7,297	3,636
Consumer \| Consumer
Allowance for Loan Losses:
Beginning Balance	1,767	1,789	1,122
Provision for loan losses	2,042	954	807
Charge- Offs	(1,411)	(1,257)	(244)
Recoveries	329	290	109
TDR Allowance Adjustments	(9)	(9)	(5)
Ending Balance	$ 2,718	$ 1,767	$ 1,789

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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-Publisher FASB
-Name Accounting Standards Codification
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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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
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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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