Pension and Other Postemployment Benefits (Details) (USD $) In Millions	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Defined Benefit Pension Plans [Member]
Components of Net Periodic Benefit Costs [Abstract]
Service cost	$ 4.1	$ 2.8
Interest cost	3.8	3.8
Expected return on plan assets	(1.8)	(1.8)
Amortization of prior service cost	2.4	2.0
Amortization of actuarial (gains) losses	0.4	0.2
Curtailments and settlements	0	1.3
Total cost	8.9	8.3
Contributions by employer	4.9	4.1
Postemployment Arrangements [Member]
Components of Net Periodic Benefit Costs [Abstract]
Service cost	2.9	1.4
Interest cost	3.5	2.9
Expected return on plan assets
Amortization of prior service cost	1.6	0.5
Amortization of actuarial (gains) losses	0.5	0.7
Total cost	$ 8.5	$ 5.5