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Note 6 - Fair Value Measurements - Change in Level 3 Liabilities (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Beginning of period fair value	$ 110.3	$ 76.3	$ 146.1	$ 117.6
Fair value adjustments	9.3	3.9	5.2	11.6
Vesting of deferred bonuses	(1.0)	0.1	(88.6)	(84.2)
Amortization of deferred bonuses	18.2	18.4	51.3	53.9
Foreign currency translation	(0.1)	2.2	2.7	2.0
Additions	0.0	4.4	20.6	4.4
End of period fair value	135.7	105.3	135.7	105.3
Contingent Consideration Liability [Member]
Settlements	$ (1.0)	$ 0.0	$ (1.6)	$ 0.0

X

- Definition

Amount of amortization of deferred bonuses 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

No definition available.

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- Definition

Amount of foreign currency translation 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

No definition available.

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- Definition

Amount of vesting of deferred bonuses 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

No definition available.

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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
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-Section 50
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of issuances 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
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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-Publisher FASB
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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
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-3

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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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- Definition

Fair value 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
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-Publisher FASB
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-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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