Components of Other Non-Operating Income (Expense), Net (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Component Of Other Expense Income Nonoperating [Line Items]
FX gain (loss)	$ 1.1	$ 20.3
Legacy tax benefit	6.4	6.4	$ 19.2
Joint venture income	11.8	9.6	8.8
Other	2.0	(0.4)	(1.5)
Other non-operating income (expense), net	$ 21.3	$ 35.9	$ 26.5