Profit Sharing, Retirement Savings Plans and Defined Benefit Pension Plans - Amounts Included in Consolidated Balance Sheets (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Other assets	$ 39.1	$ 17.8
Other current liabilities	(2.4)	(2.5)
Other liabilities	(169.4)	(182.0)
Net amount recognized	(132.7)	(166.7)
U.S.
Defined Benefit Plan Disclosure [Line Items]
Other assets	0.0	0.0
Other current liabilities	0.0	0.0
Other liabilities	(56.1)	(61.1)
Net amount recognized	(56.1)	(61.1)
International
Defined Benefit Plan Disclosure [Line Items]
Other assets	39.1	17.8
Other current liabilities	(2.4)	(2.5)
Other liabilities	(113.3)	(120.9)
Net amount recognized	$ (76.6)	$ (105.6)