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Note 9 - Pensions and Other Postretirement Benefits (Details Textual) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate | 5.10% | 5.00% |
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Settlement Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |  |  | Other income (expense), net
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement |  |  | $ 6,400
Unrecognized Actuarial Gain (Loss) in Excess of Benefit Obligation, Percentage | 10.00% |  |
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year | $ 2,900 |  |
One Percentage Point Change in Assumed Rate of Return [Member] |  |  |
Defined Benefit Plan Effect On Pension Expense |  |  | 500
One Percentage Point Increase in Discount Rate [Member] |  |  |
Defined Benefit Plan Effect On Pension Expense |  | $ 1,200 |
One Percentage Point Decrease in Discount Rate [Member] |  |  |
Defined Benefit Plan Effect On Pension Expense |  | 1,500 |
Defined Benefit Plan, Equity Securities [Member] | Minimum [Member] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 5.00% |  |
Defined Benefit Plan, Equity Securities [Member] | Maximum [Member] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 35.00% |  |
Fixed Income Securities [Member] | Minimum [Member] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 49.00% |  |
Fixed Income Securities [Member] | Maximum [Member] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 70.00% |  |
Alternative Investments [Member] | Minimum [Member] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 13.00% |  |
Alternative Investments [Member] | Maximum [Member] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 3.00% |  |
Defined Benefit Plan, Cash and Cash Equivalents [Member] | Minimum [Member] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% |  |
Defined Benefit Plan, Cash and Cash Equivalents [Member] | Maximum [Member] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 20.00% |  |
Pension Plan [Member] |  |  |
Defined Contribution Plan, Employer Discretionary Contribution Amount | $ 4,800 | 4,300 | 3,000
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement | $ (0) | $ (0) | $ (6,427)
Postretirement Health Coverage [Member] |  |  |
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate | 5.00% | 5.10% |

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- Definition Unrecognized Actuarial Gain (Loss) in Excess of Benefit Obligation, Percentage. + References No definition available. + Details
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- Definition Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-18 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Indicates line item in statement of income or comprehensive income that includes settlement gain (loss) component of net periodic benefit (cost) credit for defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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