Portfolio Loans - Summary of Aging of Recorded Investment in Past Due Portfolio Loans by Portfolio Class and Category (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Portfolio loans, including unearned loan costs	$ 2,602,156	$ 2,433,916
Non-Covered Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	6,210	4,964
90 or More Days Past Due	6,507	7,702
Total Past Due	12,717	12,666
Current	2,589,439	2,421,250
Total	2,601,180	2,433,021
Portfolio loans, including unearned loan costs	2,602,156	2,433,916
Non-Covered Loans | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	5,472	3,059
90 or More Days Past Due	1,043	232
Total Past Due	6,515	3,291
Current	1,364,580	1,266,968
Total	1,371,095	1,270,259
Non-Covered Loans | CRE - owner occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	0	766
90 or More Days Past Due	85	496
Total Past Due	85	1,262
Current	354,093	356,241
Total	354,178	357,503
Non-Covered Loans | Commercial Real Estate Investor Owned
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	577	261
90 or More Days Past Due	2,382	4,450
Total Past Due	2,959	4,711
Current	421,131	408,315
Total	424,090	413,026
Non-Covered Loans | Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	148	702
90 or More Days Past Due	2,283	2,524
Total Past Due	2,431	3,226
Current	150,548	141,547
Total	152,979	144,773
Non-Covered Loans | Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	13	168
90 or More Days Past Due	714	0
Total Past Due	727	168
Current	188,258	185,084
Total	188,985	185,252
Non-Covered Loans | Consumer and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-89 Days Past Due	0	8
90 or More Days Past Due	0	0
Total Past Due	0	8
Current	110,829	63,095
Total	109,853	62,208
Portfolio loans, including unearned loan costs	$ 110,829	$ 63,103