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Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Financial Liabilities |  |
Contingent payment obligations | $ 5.7 |
Fair Value Measured on a Recurring Basis |  |
Financial Assets |  |
Investments in equity securities | 32.3 | $ 37.9
Investments in debt securities | 24.3 | 423.1
Financial Liabilities |  |
Contingent payment obligations | 5.7 | 14.7
Affiliate equity purchase obligations | 54.8 | 53.9
Fair Value Measured on a Recurring Basis | Level 1 |  |
Financial Assets |  |
Investments in equity securities | 32.3 | 37.9
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 | Level 2 |  |
Financial Assets |  |
Investments in equity securities | 0.0 | 0.0
Investments in debt securities | 24.3 | 423.1
Financial Liabilities |  |
Contingent payment obligations | 0.0 | 0.0
Affiliate equity purchase obligations | 0.0 | 0.0
Fair Value Measured on a Recurring Basis | 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 | 5.7 | 14.7
Affiliate equity purchase obligations | $ 54.8 | $ 53.9

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