Location and Amounts of Gains and Losses on Derivative Instruments Designated as Cash Flow Hedges (Detail) - Cash flow hedges - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in Other Comprehensive Income (Loss)	$ (1.0)	$ (3.8)	$ 5.9	$ (33.9)
Gain/(Loss) Reclassified from Accumulated Other Comprehensive Loss into Income	0.8	(2.5)	(4.1)	(6.6)
Forward currency contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in Other Comprehensive Income (Loss)	(1.0)	(3.5)	5.9	(15.3)
Forward currency contracts | Cost of Goods Sold
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Reclassified from Accumulated Other Comprehensive Loss into Income	1.4	(1.2)	(2.0)	(5.9)
Option currency contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in Other Comprehensive Income (Loss)	0.0	(0.3)	0.0	(3.3)
Option currency contracts | Cost of Goods Sold
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Reclassified from Accumulated Other Comprehensive Loss into Income	0.0	(0.8)	(0.4)	0.2
Interest rate swap contract
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in Other Comprehensive Income (Loss)	0.0	0.0	0.0	(15.3)
Interest rate swap contract | Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Reclassified from Accumulated Other Comprehensive Loss into Income	$ (0.6)	$ (0.5)	$ (1.7)	$ (0.9)