Comprehensive Income (Income Tax Expense Allocated to Each Component of Other Comprehensive Income (Loss) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Other Comprehensive Income [Line Items]
Translation adjustments, Before-Tax Amount	$ 35.9	$ (102.6)	$ 16.1	$ (50.4)
Adjustment for net periodic pension post retirement benefit cost, Before-Tax Amount	10.3	6.7	13.9	108.8
Change in fair value of derivatives, Before-Tax Amount	0.2	0.2	0.8	1.0
Other comprehensive income (loss), Before-Tax Amount	46.4	(95.7)	30.8	59.4
Translation adjustments, Income Tax Expense
Adjustment for net periodic pension and postretirement benefit cost, Income Tax Expense	4.0	2.5	6.1	42.4
Change in fair value of derivatives, Income Tax Expense	0.1	0.1	0.3	0.4
Other comprehensive income (loss), Income Tax Expense	4.1	2.6	6.4	42.8
Translation adjustments, Net-of-Tax Amount	35.9	(102.6)	16.1	(50.4)
Adjustment for net periodic pension and postretirement benefit cost, Net-of-Tax Amount	6.3	4.2	7.8	66.4
Change in fair value of derivatives, Net-of-Tax Amount	0.1	0.1	0.5	0.6
Other comprehensive income (loss)	$ 42.3	$ (98.3)	$ 24.4	$ 16.6