Pensions and Postretirement Benefits Other than Pensions (Components of Net Periodic Postretirement Benefit Cost) (Details) (Postretirement Benefit Costs [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Service cost	$ 2.0	$ 2.1
Interest cost	8.1	10.4
Net amortization of prior service gains	(2.0)	(0.9)
Net amortization of plan net actuarial losses	2.5	0.7
Total	10.6	12.3
Segment, Continuing Operations [Member]
Total	6.7	8.1
Segment, Discontinued Operations [Member]
Total	$ 3.9	$ 4.2