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Note 6 - Fair Value Measurements - Changes in Level 3 Liabilities (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Beginning of period fair value | $ 146.1 | $ 117.6
Fair value adjustments | 2.8 | 5.5
Vesting of deferred bonuses | (87.1) | (81.5)
Amortization of deferred bonuses | 15.3 | 17.6
Foreign currency translation | 1.7 | (0.2)
Additions | 1.6 | 0.0
End of period fair value | 80.1 | 59.0
Contingent Consideration Liability [Member] |  |
Settlement of contingent consideration | $ (0.3) | $ 0.0

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- Definition Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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