Financial Instrument Assets/(Liabilities) Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring - Fair Value, Inputs, Level 2 - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Forward currency contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instrument assets and (liabilities) measured at fair value	$ 8.6	$ (3.3)
Option currency contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instrument assets and (liabilities) measured at fair value	0.0	3.8
Interest rate swap contract
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instrument assets and (liabilities) measured at fair value	$ 0.0	$ (7.8)