v3.25.1
Financial Instruments and Risk Management (Financial Assets and Liabilities Carried at Fair Value) (Details) - USD ($)
$ in Millions
Mar. 31, 2025
Dec. 31, 2024
Mar. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Equity securities $ 55.5 $ 55.5  
Available-for-sale fixed income investments      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Available-for-sale securities 39.0 38.0  
Level 1      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Cash equivalents 409.5 387.7  
Equity securities 55.5 55.5  
Total assets at recurring fair value measurement 465.0 443.2  
Level 1 | Money market funds      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Cash equivalents 409.5 387.7  
Level 1 | Exchange traded funds      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Equity securities 54.6 54.8  
Level 1 | Marketable securities      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Equity securities 0.9 0.7  
Level 2      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Total assets at recurring fair value measurement 191.7 299.6  
Financial and Nonfinancial Liabilities, Fair Value Disclosure 182.2 125.8  
Level 2 | Foreign currency forward contracts      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Foreign exchange derivative assets 148.5 237.5  
Foreign exchange derivative liabilities 176.8 125.8  
Level 2 | Available-for-sale fixed income investments      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Available-for-sale securities 39.0 38.0  
Level 2 | Corporate Bond Securities [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Available-for-sale securities 13.0 12.9  
Level 2 | U.S. Treasuries      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Available-for-sale securities 18.5 17.2  
Level 2 | Agency mortgage-backed securities      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Available-for-sale securities 2.9 3.2  
Level 2 | Asset-backed Securities      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Available-for-sale securities 4.3 4.4  
Level 2 | Other      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Available-for-sale securities 0.3 0.3  
Level 2 | Interest rate swaps      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Interest rate swap derivative assets 4.2 24.1  
Level 3      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Total assets at recurring fair value measurement   1,349.8 $ 1,234.0
Financial and Nonfinancial Liabilities, Fair Value Disclosure 412.2 556.1  
Level 3 | Contingent consideration      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Other Liabilities, Fair Value Disclosure 412.2    
Level 3 | Convertible Preferred Stock      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Equity Securities, FV-NI $ 1,234.0 $ 1,349.8