Other Income (Expense), Net - Details of Other income (Expense), Net (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Other Income And Expenses [Abstract]
Interest and dividend income	$ 4.3	$ 2.5	$ 10.8	$ 8.1
Net foreign exchange transaction (losses) gains	(3.7)	1.0	(8.3)	(4.4)
Bank fee expense	(1.0)	(2.3)	(4.3)	(5.6)
Other, net	4.9	(0.9)	7.6	(0.8)
Other income (expense), net	$ 4.5	$ 0.3	$ 5.8	$ (2.7)