Derivatives (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013
Not designated as hedges [Member] | Euro [Member]
Notional amounts of foreign currency forward contracts [Abstract]
Notional amounts	$ 237.4
Not designated as hedges [Member] | Canadian dollar [Member]
Notional amounts of foreign currency forward contracts [Abstract]
Notional amounts	98.0
Not designated as hedges [Member] | British pound [Member]
Notional amounts of foreign currency forward contracts [Abstract]
Notional amounts	52.0
Not designated as hedges [Member] | Australian dollar [Member]
Notional amounts of foreign currency forward contracts [Abstract]
Notional amounts	36.6
Not designated as hedges [Member] | Other [Member]
Notional amounts of foreign currency forward contracts [Abstract]
Notional amounts	157.0	[1]
Number of currency exposures within 'Other'	15
Designated as hedges [Member] | Euro [Member]
Notional amounts of foreign currency forward contracts [Abstract]
Notional amounts	392.8
Designated as hedges [Member] | Canadian dollar [Member]
Notional amounts of foreign currency forward contracts [Abstract]
Notional amounts	125.3
Designated as hedges [Member] | British pound [Member]
Notional amounts of foreign currency forward contracts [Abstract]
Notional amounts	85.5
Designated as hedges [Member] | Swiss franc [Member]
Notional amounts of foreign currency forward contracts [Abstract]
Notional amounts	43.7
Designated as hedges [Member] | Australian dollar [Member]
Notional amounts of foreign currency forward contracts [Abstract]
Notional amounts	39.2
Designated as hedges [Member] | Other [Member]
Notional amounts of foreign currency forward contracts [Abstract]
Notional amounts	49.7
Maximum [Member] | Not designated as hedges [Member] | Other [Member]
Notional amounts of foreign currency forward contracts [Abstract]
Maximum individual currency exposure within 'Other'	$ 25

[1] Comprised of exposures to 15 different currencies. None of these individual currency exposures is greater than $25 million.