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Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($)		12 Months Ended
	Aug. 31, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Apr. 01, 2024
Goodwill [Line Items]
Acquisitions and adjustments		$ 176,535,000	$ 0	$ 961,722,000
Goodwill impairment	$ 0
Impairment charges		0	0	0
Amortization of other intangible assets		$ 27,528,000	$ 24,155,000	25,857,000
Core deposit \| Minimum
Goodwill [Line Items]
Estimated useful lives		5 years
Core deposit \| Maximum
Goodwill [Line Items]
Estimated useful lives		15 years
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					10 years
Estimated fair value of intangible assets acquired		$ 46,100,000
First Midwest
Goodwill [Line Items]
Acquisitions and adjustments				961,700,000
First Midwest \| Core deposit
Goodwill [Line Items]
Estimated fair value of intangible assets acquired				77,900,000
First Midwest \| Customer trust relationships
Goodwill [Line Items]
Estimated fair value of intangible assets acquired				$ 39,700,000