Portfolio Loans - Summary of Recorded Investment by Risk Category of Portfolio Loans by Portfolio Class and Category (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross	$ 2,883,909	$ 2,750,737
Non-Covered Loans
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	2,884,159	2,750,446
Loans and Leases Receivable, Gross	2,883,909	2,750,737
Non-Covered Loans | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	1,540,457	1,484,327
Non-Covered Loans | CRE - owner occupied
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	332,639	342,959
Non-Covered Loans | Commercial Real Estate Investor Owned
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	466,713	428,064
Non-Covered Loans | Construction and land development
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	171,778	161,061
Non-Covered Loans | Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	211,155	196,498
Non-Covered Loans | Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	161,417	137,537
Loans and Leases Receivable, Gross	161,167	137,828
Pass (1-6) | Non-Covered Loans
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	2,666,324	2,541,405
Pass (1-6) | Non-Covered Loans | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	1,396,684	1,356,864
Pass (1-6) | Non-Covered Loans | CRE - owner occupied
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	302,411	314,791
Pass (1-6) | Non-Covered Loans | Commercial Real Estate Investor Owned
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	448,321	403,820
Pass (1-6) | Non-Covered Loans | Construction and land development
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	161,528	146,601
Pass (1-6) | Non-Covered Loans | Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	202,880	188,269
Pass (1-6) | Non-Covered Loans | Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	154,500	131,060
Watch (7) | Non-Covered Loans
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	134,954	149,938
Watch (7) | Non-Covered Loans | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	82,775	90,370
Watch (7) | Non-Covered Loans | CRE - owner occupied
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	27,144	24,727
Watch (7) | Non-Covered Loans | Commercial Real Estate Investor Owned
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	13,223	18,868
Watch (7) | Non-Covered Loans | Construction and land development
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	6,258	10,114
Watch (7) | Non-Covered Loans | Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	4,840	5,138
Watch (7) | Non-Covered Loans | Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	714	721
Substandard (8) | Non-Covered Loans
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	82,631	59,394
Substandard (8) | Non-Covered Loans | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	60,998	37,093
Substandard (8) | Non-Covered Loans | CRE - owner occupied
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	3,084	3,441
Substandard (8) | Non-Covered Loans | Commercial Real Estate Investor Owned
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	5,169	5,376
Substandard (8) | Non-Covered Loans | Construction and land development
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	3,992	4,346
Substandard (8) | Non-Covered Loans | Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	3,435	3,091
Substandard (8) | Non-Covered Loans | Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	5,953	6,047
Doubtful (9) | Non-Covered Loans
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	0	0
Doubtful (9) | Non-Covered Loans | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	0	0
Doubtful (9) | Non-Covered Loans | CRE - owner occupied
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	0	0
Doubtful (9) | Non-Covered Loans | Commercial Real Estate Investor Owned
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	0	0
Doubtful (9) | Non-Covered Loans | Construction and land development
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	0	0
Doubtful (9) | Non-Covered Loans | Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	0	0
Doubtful (9) | Non-Covered Loans | Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Portfolio loans	$ 0	$ 0