Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - Fair Value Measured on a Recurring Basis - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Financial Assets
Investments in marketable securities	$ 78.5	$ 74.9
Derivative financial instruments	0.9	3.5
Financial Liabilities
Total	40.3
Affiliate equity purchase obligations	12.6	22.0
Derivative financial instruments	(0.8)	4.2
Level 1
Financial Assets
Investments in marketable securities	64.5	25.7
Derivative financial instruments	0.0	0.0
Financial Liabilities
Total	0.0
Affiliate equity purchase obligations	0.0	0.0
Derivative financial instruments	0.0	0.0
Level 2
Financial Assets
Investments in marketable securities	14.0	49.2
Derivative financial instruments	0.9	3.5
Financial Liabilities
Total	0.0
Affiliate equity purchase obligations	0.0	0.0
Derivative financial instruments	(0.8)	4.2
Level 3
Financial Assets
Investments in marketable securities	0.0	0.0
Derivative financial instruments	0.0	0.0
Financial Liabilities
Total	40.3
Affiliate equity purchase obligations	12.6	22.0
Derivative financial instruments	$ 0.0	$ 0.0