Portfolio Loans - Summary of Portfolio Loans by Category (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans, including unearned loan fees	$ 3,037,705	$ 2,750,737
Portfolio loans, net
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	3,038,137	2,750,446
Unearned loan fees, net	(432)	291
Portfolio loans, including unearned loan fees	3,037,705	2,750,737
Portfolio loans, net \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	1,598,815	1,484,327
Portfolio loans, net \| Commercial - investor owned
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	515,055	428,064
Portfolio loans, net \| Commercial - owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	340,916	342,959
Portfolio loans, net \| Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	188,856	161,061
Portfolio loans, net \| Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	233,960	196,498
Portfolio loans, net \| Total real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	1,278,787	1,128,582
Portfolio loans, net \| Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	160,535	137,537
Portfolio loans, including unearned loan fees	$ 160,103	$ 137,828

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(3))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

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