Financial Instruments (Schedule of Effect of Risk Management) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Cash flow hedges:
Total	$ 228.9	$ 166.8	$ 182.8	$ 368.0
Hedged Fixed Rate Debt
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	183.5	435.1	62.3	822.8
Cross-currency interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	28.6	92.1	9.0	171.4
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	16.4	19.9	30.5	38.4
Foreign Exchange Contract
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	217.7	107.8	199.3	121.4
Forward-starting interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	84.3	57.5	141.4	337.7
Designated as Hedging Instrument \| Hedged Fixed Rate Debt
Fair value hedges:
Effect from hedged fixed-rate debt	(29.9)	(62.9)	(29.0)	(215.7)
Designated as Hedging Instrument \| Interest Rate Contracts
Fair value hedges:
Effect from interest rate contracts	29.9	62.9	29.0	215.7
Cash flow hedges:
Effective portion of losses on interest rate contracts reclassified from accumulated other comprehensive loss	3.2	4.1	10.3	12.3
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	24.7	33.1	(5.3)	75.0
Not Designated as Hedging Instrument \| Foreign Exchange Contract
Cash flow hedges:
Net losses on foreign currency exchange contracts not designated as hedging instruments	$ 201.0	$ 129.6	$ 177.8	$ 280.7

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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 of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

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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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Amount, before tax and reclassification, of gain (loss) from derivative designated and qualifying as net investment hedge.

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