Goodwill and Other Acquisition-Related Intangible Assets (Summary of Intangible Assets) (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Intangibles with finite lives
Accumulated amortization	$ (59,776)	$ (55,096)	$ (53,285)
Intangibles with indefinite lives
Gross carrying amount	83,396	83,403	83,403
Total net carrying amount	23,620	28,307	30,118
Community banking
Intangibles with indefinite lives
Total net carrying amount	19,526	22,939	24,166
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	(41,480)	(38,067)	(36,840)
Net carrying amount	13,726	17,139	18,366
Specialty finance \| Customer list intangibles
Intangibles with finite lives
Gross carrying amount	1,960	1,967	1,967
Accumulated amortization	(1,771)	(1,721)	(1,705)
Net carrying amount	189	246	262
Wealth management \| Customer list and other intangibles
Intangibles with finite lives
Gross carrying amount	20,430	20,430	20,430
Accumulated amortization	(16,525)	(15,308)	(14,740)
Net carrying amount	$ 3,905	$ 5,122	$ 5,690

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

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