v3.26.3
Financial Assets and Liabilities Subject to Recurring Fair Value Measurements (Detail) - USD ($)
$ in Millions
Sep. 30, 2026
Dec. 31, 2025
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Derivative assets $ 61.5 $ 63.0
Derivative liabilities 166.5 166.3
Fair Value, Measurements, Recurring    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 3,242.5 3,203.9
Marketable equity securities, Fair Value 5.5 3.8
Total marketable securities 3,248.0 3,207.7
Derivative assets 61.5 63.0
Derivative liabilities 166.5 166.3
Fair Value, Measurements, Recurring | Level 1    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 470.6 436.2
Marketable equity securities, Fair Value 5.5 3.8
Total marketable securities 476.1 440.0
Fair Value, Measurements, Recurring | Level 2    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 2,771.9 2,767.7
Total marketable securities 2,771.9 2,767.7
Derivative assets 61.5 63.0
Derivative liabilities 166.5 166.3
Fair Value, Measurements, Recurring | Cross currency swaps    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Derivative assets 18.2 30.0
Derivative liabilities 108.0 67.1
Fair Value, Measurements, Recurring | Cross currency swaps | Level 2    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Derivative assets 18.2 30.0
Derivative liabilities 108.0 67.1
Fair Value, Measurements, Recurring | Interest-rate swaps    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Derivative assets 14.7 20.0
Derivative liabilities 34.1 9.7
Fair Value, Measurements, Recurring | Interest-rate swaps | Level 2    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Derivative assets 14.7 20.0
Derivative liabilities 34.1 9.7
Fair Value, Measurements, Recurring | Foreign-exchange contracts    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Derivative assets 27.5 12.7
Derivative liabilities 24.3 89.5
Fair Value, Measurements, Recurring | Foreign-exchange contracts | Level 2    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Derivative assets 27.5 12.7
Derivative liabilities 24.3 89.5
Fair Value, Measurements, Recurring | Commodity contracts    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Derivative assets 1.1 0.3
Derivative liabilities 0.1  
Fair Value, Measurements, Recurring | Commodity contracts | Level 2    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Derivative assets 1.1 0.3
Derivative liabilities 0.1  
U.S. tax-exempt securities | Fair Value, Measurements, Recurring    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 225.3 344.5
U.S. tax-exempt securities | Fair Value, Measurements, Recurring | Level 2    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 225.3 344.5
U.S. taxable municipal / non-U.S. provincial bonds | Fair Value, Measurements, Recurring    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 443.8 421.6
U.S. taxable municipal / non-U.S. provincial bonds | Fair Value, Measurements, Recurring | Level 2    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 443.8 421.6
U.S. corporate securities | Fair Value, Measurements, Recurring    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 1,010.5 940.3
U.S. corporate securities | Fair Value, Measurements, Recurring | Level 2    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 1,010.5 940.3
U.S. government securities | Fair Value, Measurements, Recurring    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 470.6 436.2
U.S. government securities | Fair Value, Measurements, Recurring | Level 1    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 470.6 436.2
Non-U.S. corporate securities | Fair Value, Measurements, Recurring    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 633.2 639.7
Non-U.S. corporate securities | Fair Value, Measurements, Recurring | Level 2    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 633.2 639.7
Non-U.S. government securities | Fair Value, Measurements, Recurring    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 248.6 213.8
Non-U.S. government securities | Fair Value, Measurements, Recurring | Level 2    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 248.6 213.8
Other debt securities | Fair Value, Measurements, Recurring    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities 210.5 207.8
Other debt securities | Fair Value, Measurements, Recurring | Level 2    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable debt securities $ 210.5 $ 207.8