Cash Flow Hedge [Abstract]

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Derivative Instruments, Gain(loss) Recognized

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- Definition

Fair Value Hedge [Abstract]

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No definition available.

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- Definition

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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- Definition

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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- Definition

The effective portion of loss reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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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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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Financial Instruments (Schedule of Effect of Risk Management) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flow hedges:
Total	$ (209.7)	$ 60.7	$ 114.8
Hedged Fixed Rate Debt
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	(404.0)	40.1
Foreign currency exchange contracts
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	0.0	0.0
Forward-starting interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	(110.9)	31.6
Cross-currency interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	(207.9)	47.4
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)	(53.7)	(8.3)
Net investment hedges \| Hedged Fixed Rate Debt
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)			110.4
Net investment hedges \| Foreign currency exchange contracts
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)			5.7
Net investment hedges \| Cross-currency interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)			96.8
Cash flow hedges \| Forward-starting interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)			0.0
Cash flow hedges \| Cross-currency interest rate swaps
Cash flow hedges:
Effective portion of risk-management instruments that was recognized in other comprehensive income (loss)			0.0
Designated as Hedging Instrument \| Hedged Fixed Rate Debt
Fair value hedges:
Effect from hedged fixed-rate debt	86.9	112.1	(40.9)
Designated as Hedging Instrument \| Interest Rate Contract
Fair value hedges:
Effect from interest rate contracts	(86.9)	(112.1)	40.9
Cash flow hedges:
Effective portion of losses on interest rate contracts reclassified from accumulated other comprehensive loss	16.4	15.9
Effective portion of losses on interest rate contracts reclassified from accumulated other comprehensive loss			14.8
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	(102.4)	(17.1)
Effective portion of losses on interest rate contracts reclassified from accumulated other comprehensive loss			0.0
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	$ (123.7)	$ 61.9	$ 100.0