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, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 19,797	$ 13,772	$ 15,405	$ 12,567
Provision for loan losses	572	2,819	9,697	4,247
Charge-offs	(1,162)	(1,972)	(6,560)	(2,818)
Recoveries	1,160	293	1,825	916
Ending Balance	20,367	14,912	20,367	14,912
Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	2,506	1,792	1,813	1,489
Provision for loan losses	58	123	888	413
Charge-offs		(4)	(137)	(5)
Recoveries		1		15
Ending Balance	2,564	1,912	2,564	1,912
Construction, land development, land
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	915	181	465	367
Provision for loan losses	210	44	1,235	(142)
Charge-offs			(582)
Recoveries		7	7	7
Ending Balance	1,125	232	1,125	232
1-4 family residential properties
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	149	259	253	274
Provision for loan losses	111	(10)	16	(38)
Charge-offs	(1)		(29)	(63)
Recoveries	23	6	42	82
Ending Balance	282	255	282	255
Farmland
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	261	143	170	134
Provision for loan losses	(22)	(22)	69	(13)
Ending Balance	239	121	239	121
Commercial Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	10,603	6,697	8,014	5,276
Provision for loan losses	(629)	2,521	4,660	3,680
Charge-offs	(755)	(1,615)	(3,833)	(1,784)
Recoveries	929	217	1,307	648
Ending Balance	10,148	7,820	10,148	7,820
Factored receivables
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	4,507	4,204	4,088	4,509
Provision for loan losses	645	(7)	1,978	77
Charge-offs	(136)	(285)	(1,102)	(743)
Recoveries	30	33	82	102
Ending Balance	5,046	3,945	5,046	3,945
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	627	293	420	216
Provision for loan losses	208	114	813	313
Charge-offs	(270)	(68)	(877)	(223)
Recoveries	178	29	387	62
Ending Balance	743	368	743	368
Mortgage warehouse
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	229	203	182	302
Provision for loan losses	(9)	56	38	(43)
Ending Balance	$ 220	$ 259	$ 220	$ 259

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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