Gains and Losses Recorded in Consolidated Statement of Income related to Derivative Instruments Not Formally Designated as Hedges (Detail) (Nondesignated, USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Derivative Gain/(Loss) Recognized in Income	$ 1.5	$ (1.6)	$ 0.8	$ (4.6)
Credit Default Swap Contracts | Others Operating Income
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Derivative Gain/(Loss) Recognized in Income				(0.1)
Foreign Exchange Contracts | Others Operating Income
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Derivative Gain/(Loss) Recognized in Income	$ 1.5	$ (1.6)	$ 0.8	$ (4.5)