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Goodwill and Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Mar. 20, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Jun. 30, 2023 | Dec. 31, 2024 | Dec. 31, 2023
Finite Lived Intangible Assets [Line Items] |  |  |  |  |  |
Goodwill, net |  |  |  |  | $ 203,391 | $ 196,461
Principal balance of mortgage loans serviced for others |  |  |  |  | $ 572,600 | $ 641,200
Weighted average amortization period of intangibles |  |  |  |  | 3 years 7 months 2 days |
Core Deposit Intangibles |  |  |  |  |  |
Finite Lived Intangible Assets [Line Items] |  |  |  |  |  |
Weighted average amortization period of intangibles |  |  |  |  | 3 years 2 months 12 days |
Customer List Intangibles |  |  |  |  |  |
Finite Lived Intangible Assets [Line Items] |  |  |  |  |  |
Weighted average amortization period of intangibles |  |  |  |  | 4 years 4 months 13 days |
Mid Rivers |  |  |  |  |  |
Finite Lived Intangible Assets [Line Items] |  |  |  |  |  |
Goodwill acquired during period |  | $ 6,900 |  |  |  |
Goodwill, net |  | $ 6,930 |  |  |  |
Blackhawk Bancorp, Inc |  |  |  |  |  |
Finite Lived Intangible Assets [Line Items] |  |  |  |  |  |
Goodwill acquired during period | $ 50,100 |  | $ 50,100 |  |  |
Goodwill, net |  |  | $ 50,097 |  |  |
Purdum, Gray, Ingledue, Beck, Inc. |  |  |  |  |  |
Finite Lived Intangible Assets [Line Items] |  |  |  |  |  |
Goodwill acquired during period |  |  |  | $ 6,000 |  |
Goodwill, net |  |  |  | $ 5,951 |  |

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