Derivative Financial Instruments (Fair Value Of Derivative Instruments In Balance Sheets) (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value
Derivative assets	$ 179.1	$ 173.2
Derivative liabilities	115.9	137.1
Long-term - Derivative financial instruments - Synthetic Bonds - Call Option Premium | Long-Term - Derivative Financial Instruments
Derivatives, Fair Value
Derivative assets	43.0	62.2
Derivative liabilities	0.0	0.0
Long-term - Derivative financial instruments - Synthetic Bonds - Embedded Derivatives | Long-Term - Derivative Financial Instruments
Derivatives, Fair Value
Derivative assets	0.0	0.0
Derivative liabilities	43.0	62.2
Derivatives Designated As Hedging Instruments | Foreign exchange contracts
Derivatives, Fair Value
Derivative assets	116.5	93.6
Derivative liabilities	53.6	52.7
Derivatives Designated As Hedging Instruments | Foreign exchange contracts | Current - Derivative Financial Instruments
Derivatives, Fair Value
Derivative assets	92.6	65.6
Derivative liabilities	49.0	51.0
Derivatives Designated As Hedging Instruments | Foreign exchange contracts | Long-Term - Derivative Financial Instruments
Derivatives, Fair Value
Derivative assets	23.9	28.0
Derivative liabilities	4.6	1.7
Derivatives Not Designated As Hedging Instruments | Foreign exchange contracts
Derivatives, Fair Value
Derivative assets	19.6	17.4
Derivative liabilities	19.3	22.2
Derivatives Not Designated As Hedging Instruments | Foreign exchange contracts | Current - Derivative Financial Instruments
Derivatives, Fair Value
Derivative assets	12.0	12.7
Derivative liabilities	14.2	18.0
Derivatives Not Designated As Hedging Instruments | Foreign exchange contracts | Long-Term - Derivative Financial Instruments
Derivatives, Fair Value
Derivative assets	7.6	4.7
Derivative liabilities	$ 5.1	$ 4.2