Loans and Allowance for Loan and Lease Losses - Summary of Allowance for Loan and Lease 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	$ 24,547	$ 19,797	$ 18,748	$ 15,405
Provision for loan losses	6,803	572	14,257	9,697
Charge-offs	(4,591)	(1,162)	(6,624)	(6,560)
Recoveries	497	1,160	875	1,825
Ending Balance	27,256	20,367	27,256	20,367
Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	3,803	2,506	3,435	1,813
Provision for loan losses	136	58	506	888
Charge-offs			(2)	(137)
Recoveries	103		103
Ending Balance	4,042	2,564	4,042	2,564
Construction, land development, land
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	1,025	915	883	465
Provision for loan losses	244	210	376	1,235
Charge-offs				(582)
Recoveries	2		12	7
Ending Balance	1,271	1,125	1,271	1,125
1-4 family residential properties
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	240	149	293	253
Provision for loan losses	15	111	(29)	16
Charge-offs	(3)	(1)	(17)	(29)
Recoveries	7	23	12	42
Ending Balance	259	282	259	282
Farmland
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	509	261	310	170
Provision for loan losses	(6)	(22)	393	69
Charge-offs			(200)
Ending Balance	503	239	503	239
Commercial Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	10,230	10,603	8,150	8,014
Provision for loan losses	6,324	(629)	8,895	4,660
Charge-offs	(4,074)	(755)	(4,701)	(3,833)
Recoveries	273	929	409	1,307
Ending Balance	12,753	10,148	12,753	10,148
Factored receivables
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	7,727	4,507	4,597	4,088
Provision for loan losses	64	645	3,850	1,978
Charge-offs	(228)	(136)	(928)	(1,102)
Recoveries	8	30	52	82
Ending Balance	7,571	5,046	7,571	5,046
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	670	627	783	420
Provision for loan losses	93	208	287	813
Charge-offs	(286)	(270)	(776)	(877)
Recoveries	104	178	287	387
Ending Balance	581	743	581	743
Mortgage warehouse
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	343	229	297	182
Provision for loan losses	(67)	(9)	(21)	38
Ending Balance	$ 276	$ 220	$ 276	$ 220

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

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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.

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

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