Pension and Other Postemployment Benefits (Details) (USD $) In Millions	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Components of Net Periodic Benefit Costs [Abstract]
Contributions by employer	$ 1.2	$ 0.7
Defined Benefit Pension Plans [Member]
Components of Net Periodic Benefit Costs [Abstract]
Service cost	2.3	2.1
Interest cost	2.5	2.6
Expected return on plan assets	(1.2)	(1.3)
Amortization of prior service cost	1.5	1.3
Amortization of actuarial (gains) losses	0.3	0.2
Curtailments and settlements	0	1.3
Total cost	5.4	6.2
Postemployment Arrangements [Member]
Components of Net Periodic Benefit Costs [Abstract]
Service cost	1.9	0.9
Interest cost	2.4	1.9
Expected return on plan assets
Amortization of prior service cost	1.1	0.3
Amortization of actuarial (gains) losses	0.3	0.5
Total cost	$ 5.7	$ 3.6