Restructuring, Impairment and Other Charges, net - Schedule of Restructuring and Other Charges by Segment Recognized in Results of Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Restructuring Cost And Reserve [Line Items]
Employee Terminations	$ 2.3	$ 0.3	$ 4.0	$ 3.2
Other Restructuring Charges	0.2	0.2	0.3	0.8
Impairment Charges		2.8		2.8
Other Charges	0.1		0.3	0.1
Total	2.6	3.3	4.6	6.9
Capital Markets - Software Solutions
Restructuring Cost And Reserve [Line Items]
Employee Terminations	0.1	0.2	1.1	0.3
Other Restructuring Charges	0.0	0.0	0.0	0.0
Impairment Charges		0.0		0.0
Other Charges	0.0		0.0	0.0
Total	0.1	0.2	1.1	0.3
Capital Markets - Compliance and Communications Management
Restructuring Cost And Reserve [Line Items]
Employee Terminations	1.8	(0.1)	2.1	0.4
Other Restructuring Charges	0.0	0.0	0.0	0.0
Impairment Charges		2.8		2.8
Other Charges	0.0		0.1	0.1
Total	1.8	2.7	2.2	3.3
Investment Companies - Software Solutions
Restructuring Cost And Reserve [Line Items]
Employee Terminations	0.1		0.2	0.1
Other Restructuring Charges	0.0		0.0	0.0
Impairment Charges				0.0
Other Charges	0.0		0.0	0.0
Total	0.1		0.2	0.1
Investment Companies - Compliance and Communications Management
Restructuring Cost And Reserve [Line Items]
Employee Terminations	0.2	0.1	0.3	2.1
Other Restructuring Charges	0.2	0.2	0.3	0.8
Impairment Charges		0.0		0.0
Other Charges	0.0		0.0	0.0
Total	0.4	0.3	0.6	2.9
Corporate
Restructuring Cost And Reserve [Line Items]
Employee Terminations	0.1	0.1	0.3	0.3
Other Restructuring Charges	0.0	0.0	0.0	0.0
Impairment Charges		0.0		0.0
Other Charges	0.1		0.2	0.0
Total	$ 0.2	$ 0.1	$ 0.5	$ 0.3