Restructuring and Other - Schedule of Net Restructuring and Other Expenses (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Restructuring Cost And Reserve [Line Items]
Employee Terminations	$ 3.2	$ 6.4
Other Restructuring Charges	1.6	1.6
Total Restructuring Charges	4.8	8.0
Other	(4.6)	0.5
Multi-Employer Pension Plan Charges	0.6	0.6
Total	0.8	9.1
Total Operating Segments | Business Services
Restructuring Cost And Reserve [Line Items]
Employee Terminations	1.8	3.8
Other Restructuring Charges	1.0	1.1
Total Restructuring Charges	2.8	4.9
Other	(4.9)
Multi-Employer Pension Plan Charges	0.5	0.5
Total	(1.6)	5.4
Total Operating Segments | Marketing Solutions
Restructuring Cost And Reserve [Line Items]
Employee Terminations	1.1	1.1
Other Restructuring Charges		0.4
Total Restructuring Charges	1.1	1.5
Other	0.3	0.5
Multi-Employer Pension Plan Charges	0.1	0.1
Total	1.5	2.1
Corporate
Restructuring Cost And Reserve [Line Items]
Employee Terminations	0.3	1.5
Other Restructuring Charges	0.6	0.1
Total Restructuring Charges	0.9	1.6
Total	$ 0.9	$ 1.6