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Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($)		12 Months Ended
	Aug. 31, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	May 01, 2025	Apr. 01, 2024
Goodwill [Line Items]
Acquisitions and adjustments		$ 250,449,000	$ 176,535,000	$ 0
Goodwill impairment	$ 0
Impairment charges		0	0	0
Amortization of intangibles		$ 78,660,000	27,528,000	$ 24,155,000
Minimum \| Core deposit
Goodwill [Line Items]
Estimated useful lives of core deposits and customer relationships		5 years
Maximum \| Core deposit
Goodwill [Line Items]
Estimated useful lives of core deposits and customer relationships		15 years
Bremer
Goodwill [Line Items]
Acquisitions and adjustments		$ 250,400,000
Bremer \| Core deposit
Goodwill [Line Items]
Estimated useful lives of core deposits and customer relationships					10 years
Estimated fair value of intangible assets acquired		397,100,000
Bremer \| Customer trust relationships
Goodwill [Line Items]
Estimated useful lives of core deposits and customer relationships					12 years
Estimated fair value of intangible assets acquired		$ 43,000,000.0
CapStar Financial Holdings, Inc.
Goodwill [Line Items]
Acquisitions and adjustments			176,500,000
CapStar Financial Holdings, Inc. \| Core deposit
Goodwill [Line Items]
Estimated useful lives of core deposits and customer relationships						10 years
Estimated fair value of intangible assets acquired			$ 46,100,000