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Fair Value Measurements - Quantitative Information used in Valuing Level 3 Liabilities (Details) - Significant Unobservable Inputs (Level 3) $ in Millions	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Contingent payment obligations | Monte Carlo Simulation
Quantitative information for Level 3 Fair Value Measurements Liabilities
Fair Value	$ 6.5	$ 14.7
Contingent payment obligations | Monte Carlo Simulation | Volatility | Minimum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.10	0.19
Contingent payment obligations | Monte Carlo Simulation | Volatility | Maximum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.18	0.25
Contingent payment obligations | Monte Carlo Simulation | Volatility | Weighted Average
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.11	0.21
Contingent payment obligations | Monte Carlo Simulation | Discount rates
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.05	0.06
Contingent payment obligations | Monte Carlo Simulation | Discount rates | Weighted Average
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.05	0.06
Affiliate equity purchase obligations | Discounted cash flow
Quantitative information for Level 3 Fair Value Measurements Liabilities
Fair Value	$ 58.9	$ 53.9
Affiliate equity purchase obligations | Discounted cash flow | Discount rates | Minimum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.14	0.14
Affiliate equity purchase obligations | Discounted cash flow | Discount rates | Maximum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.18	0.17
Affiliate equity purchase obligations | Discounted cash flow | Discount rates | Weighted Average
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.15	0.14
Affiliate equity purchase obligations | Discounted cash flow | Growth rates | Minimum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	(0.05)	(0.06)
Affiliate equity purchase obligations | Discounted cash flow | Growth rates | Maximum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.08	0.07
Affiliate equity purchase obligations | Discounted cash flow | Growth rates | Weighted Average
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0	0.01

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