Derivative Financial Instruments - Location and Amount of Gains and Losses Recorded in Income For Non-Desgnated Risk Management Derivative Instruments (Detail) - Nondesignated - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Amount Recognized in Income	$ (5.1)	$ (12.8)	$ (11.9)
Foreign Exchange Contracts | Others Operating Income
Derivative Instruments, Gain (Loss) [Line Items]
Amount Recognized in Income	8.2	(6.7)	(10.9)
Other Financial Derivatives | Others Operating Income
Derivative Instruments, Gain (Loss) [Line Items]
Amount Recognized in Income	$ (13.3)	$ (6.1)	$ (1.0)