Employee Benefits - Employee Benefit Plan Status (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Supplemental Plan
Defined Benefit Plan Disclosure [Line Items]
Accumulated Benefit Obligation	$ 120.9	$ 129.0
Projected Benefit Obligation	135.6	144.5	$ 121.1
Plan Assets at Fair Value	0.0	0.0
Funded Status at end of year	$ (135.6)	$ (144.5)
Weighted-Average Assumptions:
Discount Rates	4.47%	3.79%
Rate of Increase in Compensation Level	4.39%	4.39%
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Plan Assets at Fair Value	$ 1,380.1	$ 1,506.4
U.S. Plan | Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Accumulated Benefit Obligation	980.6	1,088.4
Projected Benefit Obligation	1,092.0	1,209.9	1,062.7
Plan Assets at Fair Value	1,380.1	1,506.4	1,393.5
Funded Status at end of year	$ 288.1	$ 296.5
Weighted-Average Assumptions:
Discount Rates	4.47%	3.79%
Rate of Increase in Compensation Level	4.39%	4.39%
Expected Long-Term Rate of Return on Assets	6.00%	6.00%
Non U.S. Plans | Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Accumulated Benefit Obligation	$ 178.4	$ 192.2
Projected Benefit Obligation	183.5	198.3	155.9
Plan Assets at Fair Value	166.7	178.7	$ 139.3
Funded Status at end of year	$ (16.8)	$ (19.6)
Weighted-Average Assumptions:
Discount Rates	2.16%	2.08%
Rate of Increase in Compensation Level	1.75%	1.75%
Expected Long-Term Rate of Return on Assets	2.39%	2.61%