Components of Net Periodic Pension and Postretirement Benefit Expense (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Pension Benefits, Domestic
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 3.3	$ 3.7
Expected return on plan assets	(4.2)	(4.1)
Amortization, net	1.9	1.8
Net periodic cost	1.0	1.4
Pension Benefits, Foreign
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.5	0.5
Interest cost	0.6	0.6
Expected return on plan assets	(0.3)	(0.3)
Amortization, net	0.1
Net periodic cost	0.9	0.8
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.5	0.5
Interest cost	3.9	4.3
Expected return on plan assets	(4.5)	(4.4)
Amortization, net	2.0	1.8
Net periodic cost	1.9	2.2
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Interest cost	0.1	0.1
Amortization, net	$ (0.1)	$ (0.1)