Income Tax Expense Allocated to Each Component of Other Comprehensive Income (Loss) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Other Comprehensive Income [Line Items]
Translation adjustments, Before-Tax Amount	$ 7.1	$ 41.8
Adjustment for net periodic pension and postretirement benefit cost, Before-Tax Amount	7.8	1.6
Change in fair value of derivatives, Before-Tax Amount	0.1	0.5
Other comprehensive income, Before-Tax Amount	15.0	43.9
Translation adjustments, Income Tax Expense	0	0
Adjustment for net periodic pension and postretirement benefit cost, Income Tax Expense	8.7	0.9
Change in fair value of derivatives, Income Tax Expense		0.2
Other comprehensive income, Income Tax Expense	8.7	1.1
Translation adjustments, Net-of-Tax Amount	7.1	41.8
Adjustment for net periodic pension and postretirement benefit cost, Net-of-Tax Amount	(0.9)	0.7
Change in fair value of derivatives, Net-of-Tax Amount	0.1	0.3
Other comprehensive income	$ 6.3	$ 42.8