Portfolio Loans - Summary of Allowance for Loan Losses for Non-covered Loans by Portfolio Class and Category (Details) (Non-Covered Loans, USD $) In Thousands, unless otherwise specified	3 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014
Allowance for Loan Losses [Roll Forward]
Balance	$ 28,422	$ 27,905	$ 27,289
Provision charged to expense	66	1,348	1,027
Losses charged off	(865)	(1,093)	(1,369)
Recoveries	1,177	262	958
Balance	28,800	28,422	27,905
Commercial and industrial
Allowance for Loan Losses [Roll Forward]
Balance	15,075	12,858	12,246
Provision charged to expense	169	3,068	899
Losses charged off	(215)	(1,005)	(474)
Recoveries	880	154	187
Balance	15,909	15,075	12,858
Commercial real estate - Owner occupied
Allowance for Loan Losses [Roll Forward]
Balance	4,021	4,357	4,096
Provision charged to expense	(245)	(262)	589
Losses charged off	(50)	(88)	(336)
Recoveries	8	14	8
Balance	3,734	4,021	4,357
Commercial real estate - Investor owned
Allowance for Loan Losses [Roll Forward]
Balance	4,330	6,375	6,600
Provision charged to expense	(101)	(2,064)	(9)
Losses charged off	0	0	(250)
Recoveries	23	19	34
Balance	4,252	4,330	6,375
Construction and land development
Allowance for Loan Losses [Roll Forward]
Balance	2,155	1,987	2,136
Provision charged to expense	321	132	(532)
Losses charged off	(600)	0	(305)
Recoveries	35	36	688
Balance	1,911	2,155	1,987
Residential real estate
Allowance for Loan Losses [Roll Forward]
Balance	2,527	2,076	2,019
Provision charged to expense	(110)	412	16
Losses charged off	0	0	0
Recoveries	230	39	41
Balance	2,647	2,527	2,076
Consumer and other
Allowance for Loan Losses [Roll Forward]
Balance	314	252	192
Provision charged to expense	32	62	64
Losses charged off	0	0	(4)
Recoveries	1	0	0
Balance	$ 347	$ 314	$ 252