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v3.25.4

Basis of Presentation and Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands, shares in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
May 31, 2025 | Apr. 30, 2024 | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Property, Plant and Equipment [Line Items] |  |  |  |  |
FDIC assessment |  |  | $ 48,394 | $ 44,681 | $ 56,730
Issuance of common stock (in shares) |  |  | 1,033,262 | 417,598 |
CapStar Financial Holdings, Inc. |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Shares issued for acquisition (in shares) |  | 24.0 |  |  |
Issuance of common stock (in shares) |  | $ 417,600 |  |  |
Bremer |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Shares issued for acquisition (in shares) | 50.2 |  |  |  |
Issuance of common stock (in shares) | $ 1,000,000 |  |  |  |
Old National Bancorp |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
FDIC assessment |  |  | $ 3,000 | $ 3,000 | $ 19,100
Minimum |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Maturity of short-term securities sold under agreements to repurchase |  |  | 1 day |  |
Minimum | Core Deposits and Other Intangible Assets |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Estimated useful lives of core deposits and customer relationships |  |  | 5 years |  |
Minimum | Building and Building Improvements |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Useful lives for premises and equipment, years |  |  | 10 years |  |
Minimum | Furniture and Equipment |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Useful lives for premises and equipment, years |  |  | 3 years |  |
Maximum |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Maturity of short-term securities sold under agreements to repurchase |  |  | 4 days |  |
Maximum | Core Deposits and Other Intangible Assets |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Estimated useful lives of core deposits and customer relationships |  |  | 15 years |  |
Maximum | Building and Building Improvements |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Useful lives for premises and equipment, years |  |  | 39 years |  |
Maximum | Furniture and Equipment |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Useful lives for premises and equipment, years |  |  | 7 years |  |

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