Goodwill And Other Intangible Assets (Summary of Intangible Assets) (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Intangibles with finite lives
Accumulated amortization	$ (44,728)	$ (36,344)	$ (33,326)
Intangibles with indefinite lives
Gross carrying amount	83,398	83,401	76,983
Total net carrying amount	38,670	47,057	43,657
Community banking
Intangibles with indefinite lives
Total net carrying amount	29,797	34,680	29,963
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	48,791
Accumulated amortization	(31,209)	(26,326)	(24,628)
Net carrying amount	23,997	28,880	24,163
Customer list intangibles \| Specialty finance
Intangibles with finite lives
Gross carrying amount	1,962	1,965	1,962
Accumulated amortization	(1,624)	(1,552)	(1,526)
Net carrying amount	338	413	436
Customer list and other intangibles \| Wealth management
Intangibles with finite lives
Gross carrying amount	20,430	20,430	20,430
Accumulated amortization	(11,895)	(8,466)	(7,172)
Net carrying amount	$ 8,535	$ 11,964	$ 13,258

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

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