Accrued Liabilities (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Accrued Liabilities, Current [Abstract]
Payroll and other employee liabilities	$ 156.4	$ 161.4
Taxes, except income taxes	96.8	92.8
Retirement benefits (see note 3)	31.5	12.2
Workers' compensation and other claims	27.0	19.9
Amounts held by cash logistics operations	25.1	38.5
Income taxes payable	14.7	17.2
Other	137.0	127.0
Accrued liabilities	$ 488.5	$ 469.0