Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, net	$ 43,909	$ 34,376
Finite-Lived Intangible Assets-Future Amortization Expense [Abstract]
2016	4,214
2017	3,756
2018	3,078
2019	2,816
2020	2,816
Thereafter	27,229
Goodwill [Roll Forward]
Goodwill, Gross Beginning Balance	378,008	359,987
Goodwill, Accumulated Impairment Beginning Balance	(228)	(228)
Goodwill, Net Beginning Balance	377,780	359,759
Goodwill acquired during 2014		18,021
Goodwill acquired during 2015	7,681
Goodwill, Gross Ending Balance	385,689	378,008
Goodwill, Accumulated Impairment Ending Balance	(228)	(228)
Goodwill, Net Ending Balance	385,461	377,780
Commercial [Member]
Goodwill [Roll Forward]
Goodwill, Gross Beginning Balance	269,363	268,942
Goodwill, Accumulated Impairment Beginning Balance	0	0
Goodwill, Net Beginning Balance	269,363	268,942
Goodwill acquired during 2014		421
Goodwill acquired during 2015	7,681
Goodwill, Gross Ending Balance	277,044	269,363
Goodwill, Accumulated Impairment Ending Balance	0	0
Goodwill, Net Ending Balance	277,044	269,363
Consumer [Member]
Goodwill [Roll Forward]
Goodwill, Gross Beginning Balance	39,251	39,251
Goodwill, Accumulated Impairment Beginning Balance	(228)	(228)
Goodwill, Net Beginning Balance	39,023	39,023
Goodwill acquired during 2014		0
Goodwill acquired during 2015	0
Goodwill, Gross Ending Balance	39,251	39,251
Goodwill, Accumulated Impairment Ending Balance	(228)	(228)
Goodwill, Net Ending Balance	39,023	39,023
Wealth Management [Member]
Goodwill [Roll Forward]
Goodwill, Gross Beginning Balance	69,394	51,794
Goodwill, Accumulated Impairment Beginning Balance	0	0
Goodwill, Net Beginning Balance	69,394	51,794
Goodwill acquired during 2014		17,600
Goodwill acquired during 2015	0
Goodwill, Gross Ending Balance	69,394	69,394
Goodwill, Accumulated Impairment Ending Balance	0	0
Goodwill, Net Ending Balance	69,394	69,394
Core deposits premiums [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	33,749	33,749
Accumulated amortization	33,481	33,088
Finite-lived intangible assets, net	268	661
Finite-Lived Intangible Assets-Future Amortization Expense [Abstract]
2016	247
2017	21
2018	0
2019	0
2020	0
Thereafter	0
Other identifiable intangible assets [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	63,689	50,288
Accumulated amortization	20,048	16,573
Finite-lived intangible assets, net	43,641	$ 33,715
Finite-Lived Intangible Assets-Future Amortization Expense [Abstract]
2016	3,967
2017	3,735
2018	3,078
2019	2,816
2020	2,816
Thereafter	$ 27,229