Portfolio Loans - Summary of Portfolio Loans by Category (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans, including unearned loan costs	$ 2,435,559	$ 2,433,916
Non-Covered Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	2,434,594	2,433,021
Unearned loan costs, net	965	895
Portfolio loans, including unearned loan costs	2,435,559	2,433,916
Non-Covered Loans \| Construction and land development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	138,924	144,773
Non-Covered Loans \| Commercial - Investor Owned
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	413,170	413,026
Non-Covered Loans \| Commercial - Owner Occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	368,313	357,503
Non-Covered Loans \| Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	180,253	185,252
Non-Covered Loans \| Total real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	1,100,660	1,100,554
Non-Covered Loans \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	1,265,104	1,270,259
Non-Covered Loans \| Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Portfolio loans	68,830	62,208
Portfolio loans, including unearned loan costs	$ 69,795	$ 63,103

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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.

+ 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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- 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Subparagraph 3

-Article 9

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- Definition

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

+ Details

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- Details

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