Loans and Allowance for Loan and Lease Losses - Schedule of Recorded Investment and Unpaid Principal for Impaired Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	$ 2,810,856	$ 2,027,624
Unpaid Principal	2,832,506	2,045,606
Difference	(21,650)	(17,982)
Allowance for loan and lease losses	(18,748)	(15,405)	$ (12,567)	$ (8,843)
Loans, net	2,792,108	2,012,219
Commercial real estate
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	745,893	442,237
Unpaid Principal	753,803	447,926
Difference	(7,910)	(5,689)
Allowance for loan and lease losses	(3,435)	(1,813)	(1,489)	(533)
Construction, land development, land
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	134,812	109,812
Unpaid Principal	138,045	113,211
Difference	(3,233)	(3,399)
Allowance for loan and lease losses	(883)	(465)	(367)	(333)
1-4 family residential properties
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	125,827	104,974
Unpaid Principal	127,499	106,852
Difference	(1,672)	(1,878)
Allowance for loan and lease losses	(293)	(253)	(274)	(215)
Farmland
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	180,141	141,615
Unpaid Principal	184,006	142,673
Difference	(3,865)	(1,058)
Allowance for loan and lease losses	(310)	(170)	(134)	(19)
Commercial Loans
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	920,812	778,643
Unpaid Principal	924,133	783,349
Difference	(3,321)	(4,706)
Allowance for loan and lease losses	(8,150)	(8,014)	(5,276)	(4,003)
Factored receivables
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	374,410	238,198
Unpaid Principal	376,046	239,432
Difference	(1,636)	(1,234)
Allowance for loan and lease losses	(4,597)	(4,088)	(4,509)	(3,462)
Consumer
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	31,131	29,764
Unpaid Principal	31,144	29,782
Difference	(13)	(18)
Allowance for loan and lease losses	(783)	(420)	(216)	(140)
Mortgage warehouse
Accounts Notes And Loans Receivable [Line Items]
Loan, Total	297,830	182,381
Unpaid Principal	297,830	182,381
Allowance for loan and lease losses	$ (297)	$ (182)	$ (302)	$ (138)

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.

+ References

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-Publisher FASB
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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