Goodwill and Other Acquisition-Related Intangible Assets (Summary of Intangible Assets) (Detail) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Intangibles with finite lives
Accumulated amortization	$ (62,447)	$ (61,212)	$ (56,705)
Intangibles with indefinite lives
Gross carrying amount	83,398	83,398	83,404
Total net carrying amount	20,951	22,186	26,699
Community banking
Intangibles with indefinite lives
Total net carrying amount	17,533	18,505	21,763
Community banking \| Trademark
Intangibles with indefinite lives
Carrying amount	5,800	5,800	5,800
Community banking \| Core deposit intangibles
Intangibles with finite lives
Gross carrying amount	55,206	55,206	55,206
Accumulated amortization	(43,473)	(42,501)	(39,243)
Net carrying amount	11,733	12,705	15,963
Specialty finance \| Customer list intangibles
Intangibles with finite lives
Gross carrying amount	1,962	1,962	1,968
Accumulated amortization	(1,799)	(1,785)	(1,738)
Net carrying amount	163	177	230
Wealth management \| Customer list and other intangibles
Intangibles with finite lives
Gross carrying amount	20,430	20,430	20,430
Accumulated amortization	(17,175)	(16,926)	(15,724)
Net carrying amount	$ 3,255	$ 3,504	$ 4,706

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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