Goodwill And Other Intangible Assets (Goodwill Assets by Business Segment) (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 498,587
Goodwill Acquired	999
Impairment Loss	0
Goodwill Adjustments	674
Ending balance	500,260
Community banking
Goodwill [Roll Forward]
Beginning balance	427,781
Goodwill Acquired	999
Impairment Loss	0
Goodwill Adjustments	(152)
Ending balance	428,628
Specialty finance
Goodwill [Roll Forward]
Beginning balance	38,692
Goodwill Acquired	0
Impairment Loss	0
Goodwill Adjustments	826
Ending balance	39,518
Wealth management
Goodwill [Roll Forward]
Beginning balance	32,114
Goodwill Acquired	0
Impairment Loss	0
Goodwill Adjustments	0
Ending balance	$ 32,114