Pensions and Postretirement Benefits Other Than Pensions (Schedule of Company's Postretirement Plans Benefit Obligations) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011 Postretirement [Member]		Dec. 31, 2010 Postretirement [Member]
Benefit obligation at beginning of year		$ 883.0		$ 979.4
Service cost		8.4		8.9
Interest cost		42.0		48.1
Plan participants' contributions		20.5		20.7
Actuarial (gains) losses	8.5	63.3		(86.2)
Benefits paid, net of Medicare Part D subsidy		(81.2)	[1]	(83.4)	[1]
Settlements/curtailments		(12.7)		0
Amendments		(2.2)		(5.5)
Other, including expenses paid		(1.2)		1.0
Benefit obligation at end of year		$ 919.9		$ 883.0

[1] Amounts are net of Medicare Part D subsidy of $7.4 and $7.9 million in 2011 and 2010, respectivel