Components of Net Periodic Pension and Postretirement Benefit Expense (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Pension Benefits, Domestic
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 2.9	$ 3.6	$ 8.7	$ 10.9
Expected return on plan assets	(4.1)	(4.4)	(12.3)	(13.1)
Amortization, net	1.5	1.3	4.3	3.7
Net periodic expense	0.3	0.5	0.7	1.5
Total Pension Cost	0.3	0.5	0.7	1.5
Pension Benefits, Foreign
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.5	0.5	1.7	1.6
Interest cost	0.3	0.6	1.1	1.8
Expected return on plan assets	(0.3)	(0.3)	(0.9)	(1.0)
Amortization, net	0.3	0.1	0.9	0.3
Net periodic expense	0.8	0.9	2.8	2.7
Curtailments and settlements	0.3		0.3
Total Pension Cost	1.1	0.9	3.1	2.7
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.5	0.5	1.7	1.6
Interest cost	3.2	4.2	9.8	12.7
Expected return on plan assets	(4.4)	(4.7)	(13.2)	(14.1)
Amortization, net	1.8	1.4	5.2	4.0
Net periodic expense	1.1	1.4	3.5	4.2
Curtailments and settlements	0.3		0.3
Total Pension Cost	1.4	1.4	3.8	4.2
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Interest cost	0.1		0.2	0.2
Amortization, net	$ (0.1)	(0.1)	$ (0.2)	(0.4)
Net periodic expense		$ (0.1)		$ (0.2)