Benefits (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Benefits (Textuals) [Abstract]
Pension and Other Postretirement Benefit Contributions	$ 0	$ 0
Estimated liability of Postemployment benefits	4.0		4.0
Pension Plans, Defined Benefit [Member]
Net Periodic Benefit Cost
Service cost	4.2	5.4
Interest cost	15.1	16.4
Expected return on plan assets	(24.0)	(22.6)
Amortization of:
Prior service cost (credit)	0.6	0.6
Actuarial loss	13.6	9.9
Net Periodic Benefit Cost	9.5	9.7
Other Postretirement Benefit Plans, Defined Benefit [Member]
Net Periodic Benefit Cost
Service cost	2.7	2.8
Interest cost	3.9	5.1
Expected return on plan assets	(5.3)	(4.8)
Amortization of:
Transition obligation	0	0.1
Prior service cost (credit)	(0.5)	(0.5)
Actuarial loss	0.9	1.8
Net Periodic Benefit Cost	$ 1.7	$ 4.5