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Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($)		3 Months Ended		6 Months Ended
	Aug. 31, 2024	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	May 01, 2025	Apr. 01, 2024
Goodwill [Line Items]
Goodwill impairment	$ 0
Impairment charges				$ 0	$ 0
Amortization of other intangible assets		$ 19,630,000	$ 7,425,000	$ 26,460,000	$ 12,880,000
Minimum \| Core Deposits and Other Intangible Assets
Goodwill [Line Items]
Estimated useful lives		5 years		5 years
Maximum \| Core Deposits and Other Intangible Assets
Goodwill [Line Items]
Estimated useful lives		15 years		15 years
Bremer
Goodwill [Line Items]
Goodwill		$ 234,600,000
Bremer \| Core deposit
Goodwill [Line Items]
Estimated useful lives						10 years
Estimated fair value of intangible assets acquired		397,100,000
Bremer \| Customer relationship
Goodwill [Line Items]
Estimated useful lives						12 years
Estimated fair value of intangible assets acquired		$ 43,000,000
CapStar Financial Holdings, Inc.
Goodwill [Line Items]
Goodwill			$ 172,000,000
CapStar Financial Holdings, Inc. \| Core deposit
Goodwill [Line Items]
Estimated useful lives							10 years