Pension and Postretirement Benefit Expense (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0.5	$ 0.5	$ 1.0	$ 1.0
Interest cost	4.3	4.7	8.6	9.4
Expected return on plan assets	(4.4)	(4.2)	(8.8)	(8.5)
Amortization, net	1.8	0.8	3.6	1.6
Net periodic expense	2.2	1.8	4.4	3.5
Pension Benefits, Domestic
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.1	0.1	0.1	0.1
Interest cost	3.6	4.0	7.3	8.0
Expected return on plan assets	(4.0)	(3.9)	(8.1)	(7.8)
Amortization, net	1.7	0.8	3.5	1.6
Net periodic expense	1.4	1.0	2.8	1.9
Pension Benefits, Foreign
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.4	0.4	0.9	0.9
Interest cost	0.7	0.7	1.3	1.4
Expected return on plan assets	(0.4)	(0.3)	(0.7)	(0.7)
Amortization, net	0.1		0.1
Net periodic expense	0.8	0.8	1.6	1.6
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost		0.1		0.2
Interest cost	0.1	0.2	0.2	0.4
Amortization, net	(0.2)	(0.2)	(0.3)	(0.4)
Net periodic expense	$ (0.1)	$ 0.1	$ (0.1)	$ 0.2