Retirement Benefits (Net Amount Included In Consolidated Balance Sheets) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Noncurrent assets	$ 103.4	$ 146.3
Current liabilities	(10.5)	(4.3)
Noncurrent liabilities	(61.0)	(71.4)
Net amount at December 31	31.9	70.6
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Noncurrent assets	0.0	0.0
Current liabilities	0.0	0.0
Noncurrent liabilities	(250.3)	(298.7)
Net amount at December 31	$ (250.3)	$ (298.7)