Financial Instruments (Effect of Risk-Management Instruments) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Cash flow hedges:
Total	$ 6.3	$ 208.6
Foreign currency-denominated notes
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss), net investment hedges	54.4	207.7
Cross-currency interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss), net investment hedges	10.8	150.6
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss), cash flow hedges	17.1	26.3
Forward-starting interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss), cash flow hedges	122.5	295.1
Designated as Hedging Instrument \| Foreign currency-denominated notes
Fair value hedges:
Effect from hedged fixed-rate debt	(94.6)	(81.5)
Designated as Hedging Instrument \| Interest rate contracts
Fair value hedges:
Effect from interest rate contracts	94.6	81.5
Cash flow hedges:
Effective portion of losses on interest rate contracts reclassified from accumulated other comprehensive loss	4.1	4.1
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	8.3	71.5
Not Designated as Hedging Instrument \| Foreign currency exchange contracts
Cash flow hedges:
Net (gains) losses on foreign currency exchange contracts not designated as hedging instruments	$ (6.1)	$ 133.0

Cash Flow Hedge [Abstract]

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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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