Allowance for Loan Losses - Activity in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for Loan Losses:
Beginning Balance	$ 32,423	$ 27,122	$ 23,400
Provision for loan losses	10,999	11,730	5,648
Charge- Offs	(10,559)	(8,026)	(4,102)
Recoveries	2,420	1,789	2,495
TDR Allowance Adjustments	(129)	(192)	(319)
Ending Balance	35,154	32,423	27,122
Real Estate \| Construction and land development
Allowance for Loan Losses:
Beginning Balance	2,233	1,642	1,219
Provision for loan losses	(421)	564	(471)
Charge- Offs	0	0	0
Recoveries	31	27	896
TDR Allowance Adjustments	(1)	0	(2)
Ending Balance	1,842	2,233	1,642
Real Estate \| Commercial real estate
Allowance for Loan Losses:
Beginning Balance	11,112	9,285	9,273
Provision for loan losses	1,677	4,736	(264)
Charge- Offs	(248)	(3,139)	(407)
Recoveries	744	292	747
TDR Allowance Adjustments	(61)	(62)	(64)
Ending Balance	13,224	11,112	9,285
Real Estate \| Residential real estate
Allowance for Loan Losses:
Beginning Balance	7,775	7,131	7,483
Provision for loan losses	(231)	29	125
Charge- Offs	(152)	(80)	(569)
Recoveries	338	816	336
TDR Allowance Adjustments	(63)	(121)	(244)
Ending Balance	7,667	7,775	7,131
Commercial and financial \| Commercial and financial
Allowance for Loan Losses:
Beginning Balance	8,585	7,297	3,636
Provision for loan losses	7,969	4,359	5,304
Charge- Offs	(7,550)	(3,396)	(1,869)
Recoveries	712	325	226
TDR Allowance Adjustments	0	0	0
Ending Balance	9,716	8,585	7,297
Consumer \| Consumer
Allowance for Loan Losses:
Beginning Balance	2,718	1,767	1,789
Provision for loan losses	2,005	2,042	954
Charge- Offs	(2,609)	(1,411)	(1,257)
Recoveries	595	329	290
TDR Allowance Adjustments	(4)	(9)	(9)
Ending Balance	$ 2,705	$ 2,718	$ 1,767

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

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

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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.

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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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