Derivative Financial Instruments (Fair Value Of Derivative Instruments In Statement Of Financial Position) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative assets	$ 114.0	$ 173.2
Derivative liabilities	183.3	137.1
Foreign exchange contract
Derivatives, Fair Value [Line Items]
Derivative assets	114.0	173.2
Derivative liabilities	183.3	137.1
Call option \| Long-term – Derivative financial instruments
Derivatives, Fair Value [Line Items]
Derivative assets	9.2	62.2
Embedded derivative financial instruments \| Long-term – Derivative financial instruments
Derivatives, Fair Value [Line Items]
Derivative liabilities	9.2	62.2
Derivatives designated as hedging instruments \| Foreign exchange contract
Derivatives, Fair Value [Line Items]
Derivative assets	92.8	93.6
Derivative liabilities	163.3	52.7
Derivatives designated as hedging instruments \| Foreign exchange contract \| Current – Derivative financial instruments
Derivatives, Fair Value [Line Items]
Derivative assets	83.8	65.6
Derivative liabilities	127.7	51.0
Derivatives designated as hedging instruments \| Foreign exchange contract \| Long-term – Derivative financial instruments
Derivatives, Fair Value [Line Items]
Derivative assets	9.0	28.0
Derivative liabilities	35.6	1.7
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative assets	12.0	17.4
Derivative liabilities	10.8	22.2
Derivatives not designated as hedging instruments \| Foreign exchange contract \| Current – Derivative financial instruments
Derivatives, Fair Value [Line Items]
Derivative assets	11.9	12.7
Derivative liabilities	10.7	18.0
Derivatives not designated as hedging instruments \| Foreign exchange contract \| Long-term – Derivative financial instruments
Derivatives, Fair Value [Line Items]
Derivative assets	0.1	4.7
Derivative liabilities	0.1	4.2
Cash flow hedging \| Foreign exchange contract
Derivatives, Fair Value [Line Items]
Gain (loss) recognized in OCI (effective portion)	(75.4)	72.1	$ (86.1)
Other (expense), net \| Fair value hedging
Derivatives, Fair Value [Line Items]
Gain (loss) on fair value hedges recognized in earnings	$ (18.1)	$ 44.9	$ 32.8

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

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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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