Financial Instruments (Currency Price Risk Management Instruments) (Details) - Forward exchange contracts - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended |
|---|---|---|
Dec. 31, 2024 |
Sep. 30, 2024 |
|
| Derivative [Line Items] | ||
| US$ Notional | $ 5,869.6 | $ 6,794.6 |
| Years Average Maturity | 8 months 12 days | 9 months 18 days |
| Designated as hedging instrument | Cash flow hedges | ||
| Derivative [Line Items] | ||
| US$ Notional | $ 3,685.3 | $ 4,003.2 |
| Years Average Maturity | 6 months | 7 months 6 days |
| Designated as hedging instrument | Net investment hedges | ||
| Derivative [Line Items] | ||
| US$ Notional | $ 850.6 | $ 911.4 |
| Years Average Maturity | 2 years 2 months 12 days | 2 years 6 months |
| Not designated as hedging instrument | ||
| Derivative [Line Items] | ||
| US$ Notional | $ 1,333.7 | $ 1,880.0 |
| Years Average Maturity | 3 months 18 days | 3 months 18 days |