Defined Benefit Pension Plans (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	$ 0.8	$ 0.8	$ 2.4	$ 2.5
Interest cost	4.0	4.2	12.0	13.9
Expected return on plan assets	(4.5)	(4.8)	(13.5)	(15.4)
Amortization of prior service cost	0.1	0.1	0.3	0.3
Amortization of net loss	1.1	1.2	3.3	4.0
Net periodic pension cost	1.5	1.5	4.5	5.3
Pension expense			4.5	5.3
Pension Contributions			11.0
Defined Benefit Plan, Expected Future Benefit Payments in Year One	$ 0.5		$ 0.5