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Fair Value of Financial Instruments - Difference Between Fair Value and Unpaid Principal Balance (Details) - USD ($) | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Aggregate Fair Value | $ 6,974,000 | $ 17,515,000
Principal Balance/Amortized Cost/Contributions | 6,924,000 | 17,242,000
Difference | 50,000 | 273,000
Nonaccrual mortgage loans held for sale recorded at fair value |  | 0
Loans held for sale |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Aggregate Fair Value |  | 10,494,000
Principal Balance/Amortized Cost/Contributions |  | 10,228,000
Difference |  | 266,000
Securities carried at fair value through income |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Aggregate Fair Value | 6,203,000 | 6,512,000
Principal Balance/Amortized Cost/Contributions | 6,200,000 | 6,515,000
Difference | 3,000 | (3,000)
Rabbi Trust assets |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Aggregate Fair Value | 771,000 | 509,000
Principal Balance/Amortized Cost/Contributions | 724,000 | 499,000
Difference | $ 47,000 | $ 10,000

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