Goodwill and Other Acquisition-Related Intangible Assets - Schedule of Amortization of Finite-Lived Acquisition-Related Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025
Intangibles with finite lives
Accumulated amortization	$ (110,077)	$ (100,198)	$ (90,003)
Intangibles with indefinite lives
Gross carrying amount	198,196	198,197	200,498
Total other acquisition-related intangible assets, net	88,119	97,999	110,495
Community banking
Intangibles with indefinite lives
Total other acquisition-related intangible assets, net	83,474	92,745	104,605
Community banking \| Trademark
Intangibles with indefinite lives
Carrying amount	11,500	11,500	13,800
Community banking \| Core deposit intangibles
Intangibles with finite lives
Gross carrying amount	158,106	158,106	158,106
Accumulated amortization	(86,132)	(76,861)	(67,301)
Net carrying amount	71,974	81,245	90,805
Specialty finance \| Customer list intangibles
Intangibles with finite lives
Gross carrying amount	1,960	1,961	1,962
Accumulated amortization	(1,950)	(1,932)	(1,915)
Net carrying amount	10	29	47
Wealth management \| Customer list and other intangibles
Intangibles with finite lives
Gross carrying amount	26,630	26,630	26,630
Accumulated amortization	(21,995)	(21,405)	(20,787)
Net carrying amount	$ 4,635	$ 5,225	$ 5,843

Amount of accumulated amortization of finite-lived intangible asset. Excludes goodwill and capitalized cost for software to be sold, leased, or marketed.

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