Portfolio Loans - Summary of Recorded Investment by Risk Category of Non-covered Loans by Portfolio Class and Category (Details) (Non-Covered Loans, USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	$ 2,294,905	$ 2,137,313
Total	2,294,905	2,137,313
Pass (1-6)
Financing Receivable, Recorded Investment [Line Items]
Total	2,075,145	1,924,230
Watch (7)
Financing Receivable, Recorded Investment [Line Items]
Total	137,965	134,410
Substandard (8)
Financing Receivable, Recorded Investment [Line Items]
Total	81,424	78,032
Doubtful (9)
Financing Receivable, Recorded Investment [Line Items]
Total	371	641
Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	1,172,015	1,041,576
Commercial and industrial | Pass (1-6)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	1,066,001	977,199
Commercial and industrial | Watch (7)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	66,098	40,265
Commercial and industrial | Substandard (8)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	39,545	23,934
Commercial and industrial | Doubtful (9)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	371	178
Commercial real estate - Owner occupied
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	366,724	341,631
Commercial real estate - Owner occupied | Pass (1-6)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	337,763	306,321
Commercial real estate - Owner occupied | Watch (7)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	20,241	26,500
Commercial real estate - Owner occupied | Substandard (8)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	8,720	8,810
Commercial real estate - Owner occupied | Doubtful (9)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	0	0
Commercial real estate - Investor owned
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	391,791	437,688
Commercial real estate - Investor owned | Pass (1-6)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	353,824	368,433
Commercial real estate - Investor owned | Watch (7)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	24,295	42,227
Commercial real estate - Investor owned | Substandard (8)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	13,672	27,028
Commercial real estate - Investor owned | Doubtful (9)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	0	0
Construction and land development
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	123,888	117,032
Construction and land development | Pass (1-6)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	99,832	87,812
Construction and land development | Watch (7)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	13,547	17,175
Construction and land development | Substandard (8)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	10,509	11,582
Construction and land development | Doubtful (9)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	0	463
Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	187,594	158,527
Residential real estate | Pass (1-6)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	165,300	143,613
Residential real estate | Watch (7)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	13,730	8,240
Residential real estate | Substandard (8)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	8,564	6,674
Residential real estate | Doubtful (9)
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	0	0
Consumer and other
Financing Receivable, Recorded Investment [Line Items]
Portfolio Loans	52,893	40,859
Total	52,893	40,859
Consumer and other | Pass (1-6)
Financing Receivable, Recorded Investment [Line Items]
Total	52,425	40,852
Consumer and other | Watch (7)
Financing Receivable, Recorded Investment [Line Items]
Total	54	3
Consumer and other | Substandard (8)
Financing Receivable, Recorded Investment [Line Items]
Total	414	4
Consumer and other | Doubtful (9)
Financing Receivable, Recorded Investment [Line Items]
Total	$ 0	$ 0