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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 | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Financial Assets |  |
Investments in marketable securities | $ 81.1 | $ 78.5
Derivative financial instruments | 1.0 | 0.9
Financial Liabilities |  |
Contingent payment obligations | 31.4 | 40.3
Affiliate equity purchase obligations | 47.6 | 12.6
Derivative financial instruments | 0.9 | 0.8
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Financial Assets |  |
Investments in marketable securities | 68.2 | 64.5
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 marketable securities | 12.9 | 14.0
Derivative financial instruments | 1.0 | 0.9
Financial Liabilities |  |
Contingent payment obligations | 0.0 | 0.0
Affiliate equity purchase obligations | 0.0 | 0.0
Derivative financial instruments | 0.9 | 0.8
Significant Unobservable Inputs (Level 3) |  |
Financial Assets |  |
Investments in marketable securities | 0.0 | 0.0
Derivative financial instruments | 0.0 | 0.0
Financial Liabilities |  |
Contingent payment obligations | 31.4 | 40.3
Affiliate equity purchase obligations | 47.6 | 12.6
Derivative financial instruments | $ 0.0 | $ 0.0

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