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Note 13 - Retirement Plans (Details Textual) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Retirement Plan Expense | $ 2,600 | $ 2,500 | $ 2,200
Defined Contribution Plan [Member] |  |  |
Company Matching Percentage on First Eight Percent of Employee Contributions | 50.00% |  |
Employee Contribution Percentage for Which Company Will Match at Fifty Percent | 8.00% |  |
Pension Plan [Member] |  |  |
Number of Non-contributory Defined Benefit Plans | 2 |  |
Assets for Plan Benefits, Defined Benefit Plan | $ 900 | 500 |
Accumulated Other Comprehensive Income (Loss), Unrecognized Net Actuarial Losses, Net of Tax | 900 | 1,200 |
Defined Benefit Plan, Accumulated Benefit Obligation | 4,300 | 4,600 |
Defined Benefit Plan, Plan Assets, Amount | 5,200 | 5,100 |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) | $ 0 | $ 0 | $ 100
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate | 5.33% | 4.69% |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-Term Rate of Return on Plan Assets | 7.00% | 7.00% |
Non-qualified Retirement Savings Plan [Member] | Other Long-term Liabilities [Member] |  |  |
Deferred Compensation Liability, Classified, Noncurrent | $ 3,800 | $ 3,900 |

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