Profit Sharing, Retirement Savings Plans and Defined Benefit Pension Plans - Narrative (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Provisions charged from operations for the profit sharing plan and retirement savings plans	$ 46.3	$ 39.3	$ 36.3
Contribution of common stock to profit sharing plan (in shares)	823,567	487,108	538,524
Defined benefit pension plan corridor rate	10.00%
Plan assets	$ 836.6	$ 762.0
Equity funds
Defined Benefit Plan Disclosure [Line Items]
Plan assets	122.3	146.9
Bulk Annuity Contract
Defined Benefit Plan Disclosure [Line Items]
Plan assets	$ 131.2	119.5
Minimum | Equity funds | U.S plan
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation, percentage	65.00%
Maximum | Equity funds | U.S plan
Defined Benefit Plan Disclosure [Line Items]
Plan assets, target allocation, percentage	75.00%
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Plan assets	$ 836.6	762.0	$ 668.7
Expected contribution	18.1
Expected benefits paid	4.0
Pension Plan | U.S plan
Defined Benefit Plan Disclosure [Line Items]
Plan assets	$ 141.6	$ 137.1	119.9
Reduction in weighted average discount rate basis points	(0.50%)	(0.70%)
Pension Plan | International plan
Defined Benefit Plan Disclosure [Line Items]
Plan assets	$ 695.0	$ 624.9	$ 548.8
Reduction in weighted average discount rate basis points	(0.90%)	(1.00%)