Restructuring, Impairment and Other Charges - Schedule of Net Restructuring, Impairment and Other Charges (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restructuring Cost And Reserve [Line Items]
Employee Terminations	$ 8.4	$ 32.8	$ 22.2
Other Restructuring Charges	21.9	33.8	16.6
Impairment and Other	(7.7)	(6.6)	(5.0)
Multi-Employer Pension Plan Charges	10.7	40.0	2.9
Total	33.3	100.0	36.7
Total Operating Segments | Business Services
Restructuring Cost And Reserve [Line Items]
Employee Terminations	5.3	18.0	20.1
Other Restructuring Charges	7.8	8.7	7.4
Impairment and Other	(8.6)	(7.8)	(5.0)
Multi-Employer Pension Plan Charges	2.5	2.5	2.5
Total	7.0	21.4	25.0
Total Operating Segments | Marketing Solutions
Restructuring Cost And Reserve [Line Items]
Employee Terminations	0.3	4.6	0.5
Other Restructuring Charges	5.9	3.7	0.1
Impairment and Other	0.9	1.2
Multi-Employer Pension Plan Charges	0.4	0.4	0.4
Total	7.5	9.9	1.0
Corporate
Restructuring Cost And Reserve [Line Items]
Employee Terminations	2.8	10.2	1.6
Other Restructuring Charges	8.2	21.4	9.1
Multi-Employer Pension Plan Charges	7.8	37.1
Total	$ 18.8	$ 68.7	$ 10.7