Financial Instruments (Summary Of Assets And Liabilities) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt, including current portion	$ (1,066.8)	$ (1,075.9)
Foreign currency contract obligations	4.1
Foreign currency contract obligations		(1.8)
Natural gas contracts	(0.7)	(2.7)
Interest rate swap contracts	(8.6)	(25.7)
Quoted, Active Markets Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt, including current portion	(473.8)	(792.4)
Foreign currency contract obligations	4.1
Foreign currency contract obligations		(1.8)
Other Observable Inputs Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt, including current portion	(593.0)	(283.5)
Natural gas contracts	(0.7)	(2.7)
Interest rate swap contracts	$ (8.6)	$ (25.7)