Employee Benefit Plans Net Periodic Benefit Cost (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Pension Plan | Domestic Plan
Defined Benefit Plan and Other Postretirement Benefit Plans Disclosure
Service Cost	$ 2.3	$ 1.9	$ 4.6	$ 3.9
Interest Cost	20.0	21.1	39.9	42.2
Expected Return on Plan Assets	(26.2)	(25.7)	(52.3)	(51.5)
Amortization of Net Actuarial Loss	5.5	4.9	10.9	9.8
Amortization of Prior Service Credit	0.0	0.0	0.0	(0.1)
Net Periodic Benefit Cost	1.6	2.2	3.1	4.3
Pension Plan | Foreign Plan
Defined Benefit Plan and Other Postretirement Benefit Plans Disclosure
Service Cost	0.0	0.0	0.0	0.0
Interest Cost	1.6	1.5	3.1	3.0
Expected Return on Plan Assets	(2.3)	(1.8)	(4.7)	(3.8)
Amortization of Net Actuarial Loss	0.1	0.1	0.3	0.3
Amortization of Prior Service Credit	0.0	0.0	0.0	0.0
Net Periodic Benefit Cost	(0.6)	(0.2)	(1.3)	(0.5)
OPEB Plan
Defined Benefit Plan and Other Postretirement Benefit Plans Disclosure
Service Cost	0.0	0.0	0.0	0.0
Interest Cost	1.3	1.5	2.5	3.0
Expected Return on Plan Assets	(0.2)	(0.1)	(0.3)	(0.3)
Amortization of Net Actuarial Loss	0.0	0.0	0.0	0.0
Amortization of Prior Service Credit	0.0	(0.1)	(0.1)	(0.2)
Net Periodic Benefit Cost	$ 1.1	$ 1.3	$ 2.1	$ 2.5