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Note 7 - Other Assets (Details Textual) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Liability, Defined Benefit Plan, Noncurrent | $ 18,431 | $ 19,876 |
Cash Surrender Value, Fair Value Disclosure | 16,400 | 15,100 |
Increase (Decrease) in Cash Surrender Value | 1,300 | 1,300 | $ (2,200)
Investments Held in Rabbi Trust [Member] |  |  |
Debt Securities, Available-for-Sale, Amortized Cost | 600 | 300 |
Debt Securities, Available-for-Sale | 600 | 300 |
Supplemental Employee Retirement Plan [Member] |  |  |
Liability, Defined Benefit Plan, Noncurrent | 18,000 | 19,500 |
Investments, Fair Value Disclosure | $ 17,000 | $ 15,400 |

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