Financial Instruments (Schedule of Effect of Risk Management) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Cash flow hedges:
Total	$ 88.8	$ (61.9)
Hedged Fixed Rate Debt
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	131.8	(131.8)
Cross-currency interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	17.0	(11.8)
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	13.7	(7.8)
Foreign Exchange Contract
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	99.1	(46.1)
Forward-starting interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	77.4	23.8
Designated as Hedging Instrument \| Hedged Fixed Rate Debt
Fair value hedges:
Effect from hedged fixed-rate debt	(16.7)	35.3
Designated as Hedging Instrument \| Interest Rate Contracts
Fair value hedges:
Effect from interest rate contracts	16.7	(35.3)
Cash flow hedges:
Effective portion of losses on interest rate contracts reclassified from accumulated other comprehensive loss	2.4	3.8
Designated as Hedging Instrument \| Cross-currency interest rate swaps
Cash flow hedges:
Effective portion of losses on interest rate contracts reclassified from accumulated other comprehensive loss	84.0	(12.9)
Not Designated as Hedging Instrument \| Foreign Exchange Contract
Cash flow hedges:
Net (gains) losses on foreign currency exchange contracts not designated as hedging instruments	$ 2.4	$ (52.8)

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Derivative Instruments, Gain (Loss) Recognized

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Fair Value Hedge [Abstract]

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Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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