Financial Instruments (Schedule of Effect of Risk Management) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Cash flow hedges:
Total	$ 15.8	$ 188.8	$ (46.1)	$ 195.1
Hedged Fixed Rate Debt
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	10.6	333.3	(121.2)	387.7
Cross-currency interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	(7.8)	68.5	(19.6)	79.3
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	21.9	1.4	14.1	18.5
Foreign Exchange Contract
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	27.7	13.6	(18.4)	13.6
Forward-starting interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	33.3	157.7	57.1	280.2
Designated as Hedging Instrument \| Hedged Fixed Rate Debt
Fair value hedges:
Effect from hedged fixed-rate debt	(34.4)	(58.2)	0.9	(152.8)
Designated as Hedging Instrument \| Interest Rate Contracts
Fair value hedges:
Effect from interest rate contracts	34.4	58.2	(0.9)	152.8
Cash flow hedges:
Effective portion of losses on interest rate contracts reclassified from accumulated other comprehensive loss	3.3	4.1	7.1	8.2
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	(17.1)	33.6	(30.0)	41.9
Not Designated as Hedging Instrument \| Foreign Exchange Contract
Cash flow hedges:
Net (gains) losses on foreign currency exchange contracts not designated as hedging instruments	$ 29.6	$ 151.1	$ (23.2)	$ 145.0

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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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