Fair Value of Financial Instruments (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Forward exchange contracts, asset	$ 0	$ 0
Money market funds	174.7	134.7
Total	174.7	134.7
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Forward exchange contracts, asset	3.2	3.5
Money market funds	0	0
Total	3.2	3.5
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Forward exchange contracts, asset	0	0
Money market funds	0	0
Total	$ 0	$ 0