Restructuring, Impairment and Other - Narrative (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Restructuring Cost And Reserve [Line Items]
Employee termination costs	$ 8.1	$ 8.1
Other restructuring charges	4.2	8.2
Gain on sale of previously impaired assets	1.7
Multi-employer pension plan charges	0.7	0.7
Goodwill impairment charge	20.6
Facility Closing
Restructuring Cost And Reserve [Line Items]
Impairment of other long lived assets		$ 0.1
Business Services
Restructuring Cost And Reserve [Line Items]
Goodwill impairment charge	$ 20.6