Loans and Allowance for Loan and Lease Losses - Schedule of Recorded Investment and Unpaid Principal for Impaired Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	$ 3,608,644	$ 2,810,856
Unpaid Principal	3,630,737	2,832,506
Difference	(22,093)	(21,650)
Allowance for loan and lease losses	(27,571)	(18,748)	$ (15,405)	$ (12,567)
Loans, net	3,581,073	2,792,108
Commercial real estate
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	992,080	745,893
Unpaid Principal	999,887	753,803
Difference	(7,807)	(7,910)
Allowance for loan and lease losses	(4,493)	(3,435)	(1,813)	(1,489)
Construction, land development, land
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	179,591	134,812
Unpaid Principal	183,664	138,045
Difference	(4,073)	(3,233)
Allowance for loan and lease losses	(1,134)	(883)	(465)	(367)
1-4 family residential properties
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	190,185	125,827
Unpaid Principal	191,852	127,499
Difference	(1,667)	(1,672)
Allowance for loan and lease losses	(317)	(293)	(253)	(274)
Farmland
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	170,540	180,141
Unpaid Principal	173,583	184,006
Difference	(3,043)	(3,865)
Allowance for loan and lease losses	(535)	(310)	(170)	(134)
Commercial Loans
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	1,114,971	920,812
Unpaid Principal	1,118,028	924,133
Difference	(3,057)	(3,321)
Allowance for loan and lease losses	(12,865)	(8,150)	(8,014)	(5,276)
Factored receivables
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	617,791	374,410
Unpaid Principal	620,103	376,046
Difference	(2,312)	(1,636)
Allowance for loan and lease losses	(7,299)	(4,597)	(4,088)	(4,509)
Consumer
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	29,822	31,131
Unpaid Principal	29,956	31,144
Difference	(134)	(13)
Allowance for loan and lease losses	(615)	(783)	(420)	(216)
Mortgage warehouse
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	313,664	297,830
Unpaid Principal	313,664	297,830
Allowance for loan and lease losses	$ (313)	$ (297)	$ (182)	$ (302)

Loans and leases receivable investment net of unpaid principal.

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Loans and leases receivable unpaid principal.

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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 before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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