Interest and Other Expenses (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Other Nonoperating Income (Expense) [Abstract]
Interest expense	$ 11.2	$ 10.0	$ 32.5	$ 33.6
Interest income	(2.0)	(1.2)	(5.0)	(4.2)
Foreign exchange (gains) / losses	1.7	(0.3)	2.0	2.5
Miscellaneous expenses, net	0.1	(0.1)	4.4	1.3
Interest and other expenses	$ 11.0	$ 8.4	$ 33.9	$ 33.2