Summary of Notional Amounts of Outstanding Foreign Exchange Forwards, Cash Flow Hedging (Detail) (Forward Contracts [Member]) In Millions, unless otherwise specified	Mar. 31, 2014 Foreign Currency Forward Contracts to Purchase US Dollars with Euros [Member] USD ($)	Dec. 31, 2013 Foreign Currency Forward Contracts to Purchase US Dollars with Euros [Member] USD ($)	Mar. 31, 2014 Foreign Currency Forward Contracts To Sell US Dollars For Euros [Member] USD ($)	Dec. 31, 2013 Foreign Currency Forward Contracts To Sell US Dollars For Euros [Member] USD ($)	Mar. 31, 2014 Foreign Currency Forward Contracts to Purchase US Dollars With GBP [Member] USD ($)	Dec. 31, 2013 Foreign Currency Forward Contracts to Purchase US Dollars With GBP [Member] USD ($)	Mar. 31, 2014 Foreign Currency Forward Contracts To Purchase US Dollars With Other Foreign Currencies [Member] USD ($)	Dec. 31, 2013 Foreign Currency Forward Contracts To Purchase US Dollars With Other Foreign Currencies [Member] USD ($)	Mar. 31, 2014 Foreign Currency Forward Contracts To Purchase Euros With Other Foreign Currencies [Member] EUR (€)	Dec. 31, 2013 Foreign Currency Forward Contracts To Purchase Euros With Other Foreign Currencies [Member] EUR (€)	Mar. 31, 2014 Foreign Currency Forward Contracts To Purchase Euros With GBP [Member] EUR (€)	Dec. 31, 2013 Foreign Currency Forward Contracts To Purchase Euros With GBP [Member] EUR (€)	Mar. 31, 2014 Foreign Currency Forward Contracts to Sell Euros for GBP [Member] USD ($)	Dec. 31, 2013 Foreign Currency Forward Contracts to Sell Euros for GBP [Member] USD ($)
Derivative [Line Items]
Contracts to purchase foreign currencies	$ 80.2	$ 14.2			$ 7.1	$ 0	$ 2.4	$ 0	€ 13.1	€ 13.1	€ 22.7	€ 22.1
Contracts to sell foreign currencies			$ 54.3	$ 53.2									$ 51.2	$ 0