Comprehensive Income - Schedule of Components of Other Comprehensive Income (Loss) and Income Tax Expense Allocated to Each Component (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
Equity [Abstract]
Translation adjustments - Before Tax Amount	$ (15.0)	$ (1.1)	$ (15.3)	$ (19.8)
Adjustment for net periodic pension and other postretirement benefits plan cost - Before Tax Amount	1.4	8.5	4.8	23.9
Change in fair value of derivatives - Before Tax Amount	0	0.3	0.2	0.5
Other comprehensive income (loss) - Before Tax Amount	(13.6)	7.7	(10.3)	4.6
Adjustment for net periodic pension and other postretirement benefits plan cost - Income Tax Expense	0.4	2.9	1.5	14.4
Change in fair value of derivatives - Income Tax Expense	0	0.1	0.1	0.2
Other comprehensive income (loss) - Income Tax Expense	0.4	3.0	1.6	14.6
Translation adjustments - Net of Tax Amount	(15.0)	(1.1)	(15.3)	(19.8)
Adjustment for net periodic pension and other postretirement benefits plan cost	1.0	5.6	3.3	9.5
Change in fair value of derivatives - Net of Tax Amount	0	0.2	0.1	0.3
Other comprehensive income (loss)	$ (14.0)	$ 4.7	$ (11.9)	$ (10.0)