Goodwill and Other Acquisition-Related Intangible Assets (Summary of Intangible Assets) (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021
Intangibles with finite lives
Accumulated amortization	$ (58,284)	$ (55,096)	$ (51,408)
Intangibles with indefinite lives
Gross carrying amount	83,402	83,403	83,405
Total net carrying amount	25,118	28,307	31,997
Community banking
Intangibles with indefinite lives
Total net carrying amount	20,602	22,939	25,457
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	(40,404)	(38,067)	(35,549)
Net carrying amount	14,802	17,139	19,657
Specialty finance \| Customer list intangibles
Intangibles with finite lives
Gross carrying amount	1,966	1,967	1,969
Accumulated amortization	(1,756)	(1,721)	(1,686)
Net carrying amount	210	246	283
Wealth management \| Customer list and other intangibles
Intangibles with finite lives
Gross carrying amount	20,430	20,430	20,430
Accumulated amortization	(16,124)	(15,308)	(14,173)
Net carrying amount	$ 4,306	$ 5,122	$ 6,257

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

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