Goodwill and Other Acquisition-Related Intangible Assets - Schedule of Amortization of Finite-Lived Acquisition-Related Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022
Intangibles with finite lives
Accumulated amortization	$ (65,354)	$ (61,212)	$ (59,776)
Intangibles with indefinite lives
Gross carrying amount	89,598	83,398	83,396
Total net carrying amount	24,244	22,186	23,620
Community banking
Intangibles with indefinite lives
Total net carrying amount	15,702	18,505	19,526
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	(45,304)	(42,501)	(41,480)
Net carrying amount	9,902	12,705	13,726
Specialty finance \| Customer list intangibles
Intangibles with finite lives
Gross carrying amount	1,962	1,962	1,960
Accumulated amortization	(1,826)	(1,785)	(1,771)
Net carrying amount	136	177	189
Wealth management \| Customer list and other intangibles
Intangibles with finite lives
Gross carrying amount	26,630	20,430	20,430
Accumulated amortization	(18,224)	(16,926)	(16,525)
Net carrying amount	$ 8,406	$ 3,504	$ 3,905

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

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