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Debt (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Apr. 03, 2018	Dec. 31, 2017	Mar. 29, 2017	Oct. 31, 2013	Jun. 30, 2012	Jul. 27, 2010
Debt Instrument [Line Items]
Unamortized issuing fees	$ (11.4)		$ (13.8)
Total debt	4,191.7		3,855.0
Less: current borrowings	(67.4)		(77.1)
Long-term debt	4,124.3		3,777.9
Commercial paper
Debt Instrument [Line Items]
Long-term Debt, Gross	1,916.1		1,450.4
Synthetic bonds due 2021
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 490.9		$ 502.4
Senior notes \| 3.45% Senior Notes due 2022
Debt Instrument [Line Items]
Interest rate, stated percentage	3.45%	3.45%	3.45%	3.45%
Long-term Debt, Gross	$ 500.0		$ 500.0
Unsecured debt \| 5.00% Notes due 2020
Debt Instrument [Line Items]
Interest rate, stated percentage	5.00%		5.00%				5.00%
Long-term Debt, Gross	$ 229.0		$ 239.9
Unsecured debt \| 3.40% Notes due 2022
Debt Instrument [Line Items]
Interest rate, stated percentage	3.40%		3.40%			3.40%
Long-term Debt, Gross	$ 171.8		$ 179.9
Unsecured debt \| 3.15% Notes due 2023
Debt Instrument [Line Items]
Interest rate, stated percentage	3.15%		3.15%		3.15%
Long-term Debt, Gross	$ 148.9		$ 155.9
Unsecured debt \| 3.15% Notes due 2023
Debt Instrument [Line Items]
Interest rate, stated percentage	3.15%		3.15%		3.15%
Long-term Debt, Gross	$ 143.1		$ 149.9
Unsecured debt \| 4.00% Notes due 2027
Debt Instrument [Line Items]
Interest rate, stated percentage	4.00%		4.00%			4.00%
Long-term Debt, Gross	$ 85.9		$ 89.9
Unsecured debt \| 4.00% Notes due 2032
Debt Instrument [Line Items]
Interest rate, stated percentage	4.00%		4.00%			4.00%
Long-term Debt, Gross	$ 114.5		$ 119.9
Unsecured debt \| 3.75% Notes due 2033
Debt Instrument [Line Items]
Interest rate, stated percentage	3.75%		3.75%		3.75%
Long-term Debt, Gross	$ 114.5		$ 119.9
Bank borrowings
Debt Instrument [Line Items]
Long-term Debt, Gross	265.2		332.5
Other
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 23.2		$ 28.2