Pension and Other Post-Retirement Benefits (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Defined Benefit Pension [Member]
Components of pension and other post retirement benefit costs
Service cost	$ 1.8		$ 1.5
Interest cost	4.6		4.9
Expected return on plan assets	(6.9)		(7.4)
Amortization of unrecognized prior service credit	(0.3)	[1]	(0.3)	[1]
Amortization of unrecognized net actuarial loss (gains)	3.5	[1]	2.5	[1]
Net costs	2.7		1.2
Retiree Health and Life [Member]
Components of pension and other post retirement benefit costs
Service cost	0.1		0.1
Interest cost	0.4		0.5
Expected return on plan assets	0		0
Amortization of unrecognized prior service credit	0	[1]	0	[1]
Amortization of unrecognized net actuarial loss (gains)	0.1	[1]	0	[1]
Net costs	$ 0.6		$ 0.6

[1] Amounts are reclassified from accumulated other comprehensive loss.