Derivatives - Schedule of Pretax Effects of Derivative Financial Instruments Designated or Previously Designated as Effective Hedges (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in OCI (effective portion)	$ 5.6	$ 1.7	$ 1.0	$ 10.0
Gain/(Loss) Reclassified from AOCL to Income	0.0	(4.9)	5.2	(24.2)
Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in OCI (effective portion)	0.0	0.0	0.0	0.0
Gain/(Loss) Reclassified from AOCL to Income	(3.4)	(1.9)	(6.5)	(5.7)
Foreign currency contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in OCI (effective portion)	5.6	1.7	1.1	11.7
Gain/(Loss) Reclassified from AOCL to Income	3.4	(3.0)	11.7	(15.5)
Commodity contracts
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in OCI (effective portion)	0.0	0.0	(0.1)	0.0
Gain/(Loss) Reclassified from AOCL to Income	0.0	0.0	0.0	0.0
Cross-currency swaps
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in OCI (effective portion)	0.0	0.0	0.0	(1.7)
Gain/(Loss) Reclassified from AOCL to Income	$ 0.0	$ 0.0	$ 0.0	$ (3.0)