Other Non-Operating Interest (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Other Nonoperating Income (Expense) [Abstract]
FX gain/(loss)	$ 6.2	$ 3.8	$ 0.3	$ (5.8)
Pension Expense	2.9	2.1	5.2	3.8
Joint venture income	4.6	4.0	5.9	5.0
Other	1.2	0.5	4.5	(0.3)
Total	$ 14.9	$ 10.4	$ 15.9	$ 2.7