Loans and Allowance for Loan and Lease Losses - Summary of Allowance for Loan and Lease Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 20,022	$ 19,093	$ 18,748	$ 15,405
Provision for loan losses	4,906	1,447	7,454	9,125
Charge-offs	(567)	(1,083)	(2,033)	(5,398)
Recoveries	186	340	378	665
Ending Balance	24,547	19,797	24,547	19,797
Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	3,468	2,243	3,435	1,813
Provision for loan losses	337	263	370	830
Charge-offs	(2)		(2)	(137)
Ending Balance	3,803	2,506	3,803	2,506
Construction, land development, land
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	998	566	883	465
Provision for loan losses	25	512	132	1,025
Charge-offs		(163)		(582)
Recoveries	2		10	7
Ending Balance	1,025	915	1,025	915
1-4 family residential properties
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	248	160	293	253
Provision for loan losses	4	(25)	(44)	(95)
Charge-offs	(14)		(14)	(28)
Recoveries	2	14	5	19
Ending Balance	240	149	240	149
Farmland
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	618	214	310	170
Provision for loan losses	91	47	399	91
Charge-offs	(200)		(200)
Ending Balance	509	261	509	261
Commercial Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	9,193	11,177	8,150	8,014
Provision for loan losses	964	(504)	2,571	5,289
Charge-offs	(1)	(226)	(627)	(3,078)
Recoveries	74	156	136	378
Ending Balance	10,230	10,603	10,230	10,603
Factored receivables
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	4,493	4,064	4,597	4,088
Provision for loan losses	3,317	814	3,786	1,333
Charge-offs	(116)	(386)	(700)	(966)
Recoveries	33	15	44	52
Ending Balance	7,727	4,507	7,727	4,507
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	719	547	783	420
Provision for loan losses	110	233	194	605
Charge-offs	(234)	(308)	(490)	(607)
Recoveries	75	155	183	209
Ending Balance	670	627	670	627
Mortgage warehouse
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	285	122	297	182
Provision for loan losses	58	107	46	47
Ending Balance	$ 343	$ 229	$ 343	$ 229

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

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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

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Amount of expense related to estimated loss from loan and lease transactions.

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