Other Non-Operating Interest (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Component of Other Expense Income Nonoperating [Line Items]
FX gain/(loss)	$ 0.8	$ (12.2)	$ 4.8	$ (12.2)
Joint venture income	3.0	3.4	4.9	5.3
Other	(0.8)	0.6	(1.1)	1.2
Total	$ 3.0	$ (8.2)	$ 8.6	$ (5.7)