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Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Financial Liabilities
Contingent payment obligations	$ 0.0
Fair Value Measured on a Recurring Basis
Financial Assets
Investments in equity securities	37.1	$ 32.3
Investments in debt securities	48.4	24.3
Financial Liabilities
Contingent payment obligations	0.0	5.7
Affiliate equity purchase obligations	235.2	54.8
Fair Value Measured on a Recurring Basis | Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial Assets
Investments in equity securities	37.1	32.3
Investments in debt securities	0.0	0.0
Financial Liabilities
Contingent payment obligations	0.0	0.0
Affiliate equity purchase obligations	0.0	0.0
Fair Value Measured on a Recurring Basis | Significant Other Observable Inputs (Level 2)
Financial Assets
Investments in equity securities	0.0	0.0
Investments in debt securities	48.4	24.3
Financial Liabilities
Contingent payment obligations	0.0	0.0
Affiliate equity purchase obligations	0.0	0.0
Fair Value Measured on a Recurring Basis | Significant Unobservable Inputs (Level 3)
Financial Assets
Investments in equity securities	0.0	0.0
Investments in debt securities	0.0	0.0
Financial Liabilities
Contingent payment obligations	0.0	5.7
Affiliate equity purchase obligations	$ 235.2	$ 54.8

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481830/320-10-45-1

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