Commitments and Contingencies - Narrative (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) Facility	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Commitment And Contingencies [Line Items]
Commitments for outsourced services	$ 52.5
Operating lease commitments	258.5
Minimum non-cancelable sublease rental commitments	7.6
Rend expense for facilities in use and equipment	$ 110.0	$ 118.3	$ 117.6
Number of sites cited as potentially responsible party | Facility	2
Number of previously and currently owned sites with potential remediation obligations | Facility	6
Purchase of Property, Plant and Equipment
Commitment And Contingencies [Line Items]
Commitments for the purchase of property, plant and equipment	$ 45.0