Accumulated Other Comprehensive Income (Loss) and Other Comprehensive Income (Loss) - Schedule of Components of Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Foreign currency translation adjustments	$ 0.1	$ 11.5	$ 28.8	$ (23.5)
Tax expense (benefit)		1.7	3.4	(1.9)
Foreign currency translation adjustments, net of tax	0.1	9.8	25.4	(21.6)
Commodity hedge contracts	1.6	2.0	1.6	7.2
Equity interest in investee's other comprehensive income (loss)			(0.1)	3.9
Pre-tax amount	1.6	2.0	1.5	11.1
Tax expense	0.6	0.7	0.6	4.2
Derivative cash flow hedges, net of tax	1.0	1.3	0.9	6.9
Amortization of actuarial loss and prior service credit	(2.4)	(1.6)	(4.8)	(3.2)
Other pension and OPEB plan adjustments	0.1		0.3	0.4
Pre-tax amount	2.3	1.6	4.5	2.8
Tax benefit	(0.9)	(0.6)	(1.7)	(1.1)
Pension and OPEB liability adjustments, net of tax	(1.4)	(1.0)	(2.8)	(1.7)
Other comprehensive income (loss), before income taxes	(0.6)	11.9	25.8	(15.2)
Total tax expense (benefit) for the period	(0.3)	1.8	2.3	1.2
Other comprehensive income (loss), net of tax	$ (0.3)	$ 10.1	$ 23.5	$ (16.4)