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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 |  |  |

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