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Note 16 - Retirement Benefit Plans - Actuarial Gains and Losses (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Amortization of actuarial loss | $ 1.3 | $ 0.5 | $ 0.0
Pension Plan [Member] |  |  |
Accumulated unamortized actuarial loss | (84.7) | (70.4) |
Actuarial loss | (17.5) | (18.8) |
Tax at source on current year actuarial gain | 3.2 | 3.5 |
Prior service cost | 0.4 | 0.5 |
Amortization of actuarial loss | 1.3 | 0.5 |
Accumulated unamortized actuarial loss | $ (97.3) | $ (84.7) | $ (70.4)

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- Definition Amount of accumulated unamortized actuarial gain (loss) of defined benefit plan. + References No definition available. + Details
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- Definition Amount of accumulated unamortized actuarial gain (loss) recognized during the year before tax of defined benefit plan. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit 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 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480535/715-20-45-3A Reference 3: 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 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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