Goodwill And Other Intangible Assets (Summary of Intangible Assets) (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Intangibles with finite lives
Accumulated amortization	$ (53,285)	$ (47,362)	$ (44,728)
Intangibles with indefinite lives
Gross carrying amount	83,403	83,402	83,398
Total net carrying amount	30,118	36,040	38,670
Community banking
Intangibles with indefinite lives
Total net carrying amount	24,166	28,326	29,797
Trademark \| Community banking
Intangibles with indefinite lives
Carrying amount	5,800	5,800	5,800
Core deposit intangibles \| Community banking
Intangibles with finite lives
Gross carrying amount	55,206	55,206	55,206
Accumulated amortization	(36,840)	(32,680)	(31,209)
Net carrying amount	18,366	22,526	23,997
Customer list intangibles \| Specialty finance
Intangibles with finite lives
Gross carrying amount	1,967	1,966	1,962
Accumulated amortization	(1,705)	(1,644)	(1,624)
Net carrying amount	262	322	338
Customer list and other intangibles \| Wealth management
Intangibles with finite lives
Gross carrying amount	20,430	20,430	20,430
Accumulated amortization	(14,740)	(13,038)	(11,895)
Net carrying amount	$ 5,690	$ 7,392	$ 8,535

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

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