Goodwill and Other Acquisition-Related Intangible Assets (Goodwill Assets by Business Segment) (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2023 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 653,524
Goodwill Acquired	0
Impairment Loss	0
Goodwill Adjustments	63
Ending balance	653,587
Community banking
Goodwill [Roll Forward]
Beginning balance	545,671
Goodwill Acquired	0
Impairment Loss	0
Goodwill Adjustments	0
Ending balance	545,671
Specialty finance
Goodwill [Roll Forward]
Beginning balance	38,480
Goodwill Acquired	0
Impairment Loss	0
Goodwill Adjustments	63
Ending balance	38,543
Wealth management
Goodwill [Roll Forward]
Beginning balance	69,373
Goodwill Acquired	0
Impairment Loss	0
Goodwill Adjustments	0
Ending balance	$ 69,373

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 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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