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Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Financial Liabilities
Contingent payment obligations	$ 21.0
Fair Value Measured on a Recurring Basis
Financial Assets
Investments in equity securities	447.9	$ 64.5
Investments in debt securities	269.0	14.0
Derivative financial instruments	0.5	0.9
Financial Liabilities
Contingent payment obligations	21.0	40.3
Affiliate equity purchase obligations	24.5	12.6
Derivative financial instruments	0.9	0.8
Fair Value Measured on a Recurring Basis | Level 1
Financial Assets
Investments in equity securities	305.6	64.5
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
Fair Value Measured on a Recurring Basis | Level 2
Financial Assets
Investments in equity securities	142.3	0.0
Investments in debt securities	269.0	14.0
Derivative financial instruments	0.5	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
Fair Value Measured on a Recurring Basis | 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	21.0	40.3
Affiliate equity purchase obligations	24.5	12.6
Derivative financial instruments	$ 0.0	$ 0.0

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