Derivative Instruments (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Derivative Instruments, Gain (Loss)
Derivative Instruments, Gain (Loss) Recognized in Income, Net	$ 7.8	$ 0.3	$ (4.6)
Currency swaps
Derivative Instruments, Gain (Loss)
Derivative Instruments, Gain (Loss) Recognized in Income, Net	0	(1.8)	(5.9)
Forward exchange contracts
Derivative Instruments, Gain (Loss)
Derivative Instruments, Gain (Loss) Recognized in Income, Net	0.8	0.5	1.3
Derivatives designated as hedging instruments | Interest-rate swap
Derivative Instruments, Gain (Loss)
Derivative Instruments, Gain (Loss) Recognized in Income, Net	$ 7.0	$ 1.6	$ 0