Goodwill and Other Acquisition-Related Intangible Assets - Schedule of Amortization of Finite-Lived Acquisition-Related Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
Intangibles with finite lives
Accumulated amortization	$ (67,868)	$ (66,710)	$ (62,447)
Intangibles with indefinite lives
Gross carrying amount	89,598	89,599	83,398
Total other acquisition-related intangible assets, net	21,730	22,889	20,951
Community banking
Intangibles with indefinite lives
Total other acquisition-related intangible assets, net	14,107	14,881	17,533
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	(46,899)	(46,125)	(43,473)
Net carrying amount	8,307	9,081	11,733
Specialty finance \| Customer list intangibles
Intangibles with finite lives
Gross carrying amount	1,962	1,963	1,962
Accumulated amortization	(1,849)	(1,837)	(1,799)
Net carrying amount	113	126	163
Wealth management \| Customer list and other intangibles
Intangibles with finite lives
Gross carrying amount	26,630	26,630	20,430
Accumulated amortization	(19,120)	(18,748)	(17,175)
Net carrying amount	$ 7,510	$ 7,882	$ 3,255

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

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