Financial Instrument Assets and (Liabilities) Measured at Fair Value on Recurring Basis (Detail) (Fair Value, Measurements, Recurring, USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
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	$ 5.1	$ 1.0
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	2.0	0.6
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	$ 12.2	$ 13.3