Goodwill And Other Intangible Assets (Goodwill Assets by Business Segment) (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019
Goodwill [Roll Forward]
Beginning balance		$ 573,141
Goodwill Acquired		10,726
Impairment Loss		0
Goodwill Adjustments		1,044
Ending balance	$ 584,911	584,911
Community banking
Goodwill [Roll Forward]
Beginning balance		465,085
Goodwill Acquired	10,800	10,726
Impairment Loss		0
Goodwill Adjustments		123
Ending balance	475,934	475,934
Specialty finance
Goodwill [Roll Forward]
Beginning balance		38,343
Goodwill Acquired		0
Impairment Loss		0
Goodwill Adjustments		921
Ending balance	39,264	39,264
Wealth management
Goodwill [Roll Forward]
Beginning balance		69,713
Goodwill Acquired		0
Impairment Loss		0
Goodwill Adjustments		0
Ending balance	$ 69,713	$ 69,713

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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