Portfolio Loans - Summary of Recorded Investment by Risk Category of Portfolio Loans by Portfolio Class and Category (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	$ 3,118,392	$ 2,750,737
Non-Covered Loans
Financing Receivable, Recorded Investment [Line Items]
Total	3,119,154	2,750,446
Portfolio loans	3,118,392	2,750,737
Non-Covered Loans \| Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Total	1,632,714	1,484,327
Non-Covered Loans \| CRE - investor owned
Financing Receivable, Recorded Investment [Line Items]
Total	544,808	428,064
Non-Covered Loans \| CRE - owner occupied
Financing Receivable, Recorded Investment [Line Items]
Total	350,148	342,959
Non-Covered Loans \| Construction and land development
Financing Receivable, Recorded Investment [Line Items]
Total	194,542	161,061
Non-Covered Loans \| Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Total	240,760	196,498
Non-Covered Loans \| Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Total	156,182	137,537
Portfolio loans	155,420	137,828
Pass (1-6) \| Non-Covered Loans
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	2,909,234	2,541,405
Pass (1-6) \| Non-Covered Loans \| Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Total	1,499,114	1,356,864
Pass (1-6) \| Non-Covered Loans \| CRE - investor owned
Financing Receivable, Recorded Investment [Line Items]
Total	306,658	314,791
Pass (1-6) \| Non-Covered Loans \| CRE - owner occupied
Financing Receivable, Recorded Investment [Line Items]
Total	530,494	403,820
Pass (1-6) \| Non-Covered Loans \| Construction and land development
Financing Receivable, Recorded Investment [Line Items]
Total	185,505	146,601
Pass (1-6) \| Non-Covered Loans \| Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Total	233,479	188,269
Pass (1-6) \| Non-Covered Loans \| Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	153,984	131,060
Watch (7) \| Non-Covered Loans
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	116,686	149,938
Watch (7) \| Non-Covered Loans \| Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Total	57,416	90,370
Watch (7) \| Non-Covered Loans \| CRE - investor owned
Financing Receivable, Recorded Investment [Line Items]
Total	39,249	24,727
Watch (7) \| Non-Covered Loans \| CRE - owner occupied
Financing Receivable, Recorded Investment [Line Items]
Total	10,449	18,868
Watch (7) \| Non-Covered Loans \| Construction and land development
Financing Receivable, Recorded Investment [Line Items]
Total	6,575	10,114
Watch (7) \| Non-Covered Loans \| Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Total	2,997	5,138
Watch (7) \| Non-Covered Loans \| Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	0	721
Substandard (8) \| Non-Covered Loans
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	92,472	59,394
Substandard (8) \| Non-Covered Loans \| Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Total	76,184	37,093
Substandard (8) \| Non-Covered Loans \| CRE - investor owned
Financing Receivable, Recorded Investment [Line Items]
Total	4,241	3,441
Substandard (8) \| Non-Covered Loans \| CRE - owner occupied
Financing Receivable, Recorded Investment [Line Items]
Total	3,865	5,376
Substandard (8) \| Non-Covered Loans \| Construction and land development
Financing Receivable, Recorded Investment [Line Items]
Total	2,462	4,346
Substandard (8) \| Non-Covered Loans \| Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Total	4,284	3,091
Substandard (8) \| Non-Covered Loans \| Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	$ 1,436	$ 6,047

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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=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

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