Gains and Losses on Derivatives Designated as Hedging Instruments, Net Investment Hedging (Detail) - Net Investment Hedging [Member] - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Derivative Instruments Gain Loss [Line Items]
Amount of Gain/(Loss) Recognized in AOCI on Derivative (Effective Portion)	$ (7.6)	$ (1.6)	$ 11.3	$ (3.7)
Foreign Exchange Contract [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain/(Loss) Recognized in AOCI on Derivative (Effective Portion)	2.1	(1.6)	13.4	(3.7)
N/A
Derivative Instruments Gain Loss [Line Items]
Amount of Gain/(Loss) Reclassified from AOCI into Income (Effective Portion)	0.0	0.0	0.0
Gain/(Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0.0	0.0	0.0
long-term debt
Derivative Instruments Gain Loss [Line Items]
Amount of Gain/(Loss) Recognized in AOCI on Derivative (Effective Portion)	$ (9.7)	$ 0.0	$ (2.1)	$ 0.0