Goodwill and Other Acquisition-Related Intangible Assets - Schedule of Amortization of Finite-Lived Acquisition-Related Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025
Intangibles with finite lives
Accumulated amortization	$ (105,156)	$ (100,198)	$ (84,423)
Intangibles with indefinite lives
Gross carrying amount	198,196	198,197	200,495
Total other acquisition-related intangible assets, net	93,040	97,999	116,072
Community banking
Intangibles with indefinite lives
Total other acquisition-related intangible assets, net	88,105	92,745	109,862
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	(81,501)	(76,861)	(62,044)
Net carrying amount	76,605	81,245	96,062
Specialty finance \| Customer list intangibles
Intangibles with finite lives
Gross carrying amount	1,960	1,961	1,959
Accumulated amortization	(1,941)	(1,932)	(1,901)
Net carrying amount	19	29	58
Wealth management \| Customer list and other intangibles
Intangibles with finite lives
Gross carrying amount	26,630	26,630	26,630
Accumulated amortization	(21,714)	(21,405)	(20,478)
Net carrying amount	$ 4,916	$ 5,225	$ 6,152

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

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