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Fair Value Measurements - Quantitative Information used in Valuing Level 3 Liabilities (Details) - Significant Unobservable Inputs (Level 3) $ in Millions	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Contingent Payment Obligations | Monte Carlo Simulation
Quantitative information for Level 3 Fair Value Measurements Liabilities
Fair Value	$ 31.4	$ 40.3
Contingent Payment Obligations | Monte Carlo Simulation | Volatility | Minimum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.18	0.13
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	0.18	0.13
Contingent Payment Obligations | Monte Carlo Simulation | Discount rates | Minimum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.03	0.01
Contingent Payment Obligations | Monte Carlo Simulation | Discount rates | Maximum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.03	0.02
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	0.03	0.02
Affiliate equity purchase obligations | Discounted cash flow
Quantitative information for Level 3 Fair Value Measurements Liabilities
Fair Value	$ 47.6	$ 12.6
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	(0.13)	(0.13)
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	0.07
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	0.04	0.02
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	0.15	0.15
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	0.18
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	0.15

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Fair value of financial and nonfinancial obligations.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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