Goodwill and Other Intangible Assets Goodwill and Other Intangible Assets-Accumulated Amortization of Intangible Assets Schedule (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 96,561	$ 96,561	$ 102,151
Finite-Lived Intangible Assets, Accumulated Amortization	(30,737)	(25,541)	(25,265)
Finite-Lived Intangible Assets, Net	65,824	71,020	76,886
Core Deposits
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	82,323	82,323	87,533
Finite-Lived Intangible Assets, Accumulated Amortization	(24,150)	(19,996)	(20,637)
Finite-Lived Intangible Assets, Net	58,173	62,327	66,896
Lease Agreements
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	238	238	618
Finite-Lived Intangible Assets, Accumulated Amortization	(194)	(176)	(538)
Finite-Lived Intangible Assets, Net	44	62	80
Customer Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	14,000	14,000	14,000
Finite-Lived Intangible Assets, Accumulated Amortization	(6,393)	(5,369)	(4,090)
Finite-Lived Intangible Assets, Net	$ 7,607	$ 8,631	$ 9,910