Derivative Instruments (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2013 Notes Payable 4.5 Percent Due 2021 [Member]	Dec. 31, 2012 Notes Payable 4.5 Percent Due 2021 [Member]	Dec. 31, 2013 Derivatives not designated as hedging instruments Forward exchange contracts	Dec. 31, 2012 Derivatives not designated as hedging instruments Forward exchange contracts	Dec. 31, 2012 Derivatives designated as hedging instruments Interest-rate swap	Dec. 31, 2013 (Level 2) Measured on a recurring basis Interest-rate swap	Dec. 31, 2012 (Level 2) Measured on a recurring basis Interest-rate swap
Derivative Instruments
Derivative Liability							$ 20.2
Derivative Asset								17.0
Maximum Remaining Maturity of Foreign Currency Derivatives	6 months
Notional amounts of derivatives				5.5	6.1	400.0
Number of swap agreements						4
Debt instrument, face amount		$ 400
Fixed-rate (as a percent)			4.50%