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Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - Fair Value Measured on a Recurring Basis - USD ($) $ in Millions | Jun. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Financial Assets |  |
Investments in equity securities | $ 95.8 | $ 447.9
Investments in debt securities | 348.4 | 269.0
Derivative financial instruments | 1.9 | 0.5
Financial Liabilities |  |
Contingent payment obligations | 23.4 | 21.0
Affiliate equity purchase obligations | 68.4 | 24.5
Derivative financial instruments | 1.5 | 0.9
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Financial Assets |  |
Investments in equity securities | 95.8 | 305.6
Investments in debt securities | 0.0 | 0.0
Derivative financial instruments | 0.0 | 0.0
Financial Liabilities |  |
Contingent payment obligations | 0.0 | 0.0
Affiliate equity purchase obligations | 0.0 | 0.0
Derivative financial instruments | 0.0 | 0.0
Significant Other Observable Inputs (Level 2) |  |
Financial Assets |  |
Investments in equity securities | 0.0 | 142.3
Investments in debt securities | 348.4 | 269.0
Derivative financial instruments | 1.9 | 0.5
Financial Liabilities |  |
Contingent payment obligations | 0.0 | 0.0
Affiliate equity purchase obligations | 0.0 | 0.0
Derivative financial instruments | 1.5 | 0.9
Significant Unobservable Inputs (Level 3) |  |
Financial Assets |  |
Investments in equity securities | 0.0 | 0.0
Investments in debt securities | 0.0 | 0.0
Derivative financial instruments | 0.0 | 0.0
Financial Liabilities |  |
Contingent payment obligations | 23.4 | 21.0
Affiliate equity purchase obligations | 68.4 | 24.5
Derivative financial instruments | $ 0.0 | $ 0.0

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