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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, 2023 USD ($)	Dec. 31, 2022 USD ($)
Contingent payment obligations | Monte Carlo Simulation
Quantitative information for Level 3 Fair Value Measurements Liabilities
Fair Value	$ 18.2	$ 21.0
Contingent payment obligations | Monte Carlo Simulation | Volatility | Minimum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.19	0.18
Contingent payment obligations | Monte Carlo Simulation | Volatility | Maximum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.25	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	0.20	0.18
Contingent payment obligations | Monte Carlo Simulation | Discount rates
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.07	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	0.07	0.06
Affiliate equity purchase obligations | Discounted cash flow
Quantitative information for Level 3 Fair Value Measurements Liabilities
Fair Value	$ 45.2	$ 24.5
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	0.12	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	(0.07)	(0.03)
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	0.07	0.06
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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Fair value of financial and nonfinancial obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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