Portfolio Loans - Summary of Portfolio Loans by Category (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, including unearned loan fees	$ 4,350,001	$ 4,097,050
Non-Covered Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	4,305,626	4,024,221
Unearned loan fees, net	(2,026)	(1,325)
Loans, including unearned loan fees	4,303,600	4,022,896
Non-Covered Loans \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	2,121,008	1,918,720
Non-Covered Loans \| CRE - investor owned
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	843,728	769,275
Non-Covered Loans \| CRE - owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	604,498	554,589
Non-Covered Loans \| Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	330,097	303,091
Non-Covered Loans \| Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	298,944	341,312
Non-Covered Loans \| Total real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	2,077,267	1,968,267
Non-Covered Loans \| Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, before unearned loan fees	107,351	137,234
Loans, including unearned loan fees	$ 105,325	$ 135,909

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No definition available.

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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=82891408&loc=d3e4428-111522

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- Definition

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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