Derivative Financial Instruments Location of Gains and Losses on Derivative Financial Instruments Designated as Hedging Instruments (Detail) - Designated as Hedging Instrument - Cash Flow Hedging - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	$ 1.5	$ 7.0	$ (10.8)	$ 10.6
Interest Rate Swaps
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	(0.1)	0.1	(0.1)	(0.1)
Foreign Exchange Contracts
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	$ 1.6	$ 6.9	$ (10.7)	$ 10.7