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Fair Value of Assets and Liabilities - Additional Information (Details) - USD ($) | 9 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |  |  |
Allowance for credit losses | $ 72,925,000 | $ 68,774,000 | $ 70,182,000 | $ 71,160,000 | $ 68,312,000 | $ 68,675,000
Other real estate owned | 1,463,000 |  | 2,179,000 |  |  |
Mortgage Servicing Rights |  |  |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |  |  |
Finite-lived intangible assets, net | 4,823,000 | 5,835,000 | 5,629,000 |  |  | $ 6,859,000
Mortgage servicing rights (MSR) impairment (recovery) | 1,000 | $ (77,000) | $ 7,000 |  |  |
Fair Value, Nonrecurring |  |  |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |  |  |
Carrying amount of loans with a specific allowance | 5,800,000 |  |  |  |  |
Fair value of loans with a specific allowance | 5,400,000 |  |  |  |  |
Allowance for credit losses | 412,000 |  |  |  |  |
Fair Value, Nonrecurring | Carrying Amount |  |  |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |  |  |
Other real estate owned | 1,500,000 |  |  |  |  |
Fair Value, Nonrecurring | Fair Value |  |  |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |  |  |
Other real estate owned | $ 948,000 |  |  |  |  |

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