Other Non-current Liabilities (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Other Liabilities, Noncurrent [Abstract]
Income taxes payable	$ 58.9	$ 78.3
Deferred revenue	11.4	12.2
Deferred rent	11.9	14.0
Insurance provisions	12.3	14.5
Contingent consideration payable	120.4	0
Other non-current liabilities	26.7	25.3
Other noncurrent liabilities, total	$ 241.6	$ 144.3