Goodwill and Other Intangible Assets - Goodwill Balances by Reportable Segment (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Goodwill [Line Items]
Goodwill, Gross			$ 450.6
Accumulated impairment charges			(40.6)	$ (40.6)
Goodwill, beginning balance		$ 410.0
Disposition	[1]	(3.5)
Foreign exchange and other adjustments		(0.7)
Goodwill, ending balance		405.8
Capital Markets - Software Solutions
Goodwill [Line Items]
Goodwill, Gross			103.7
Accumulated impairment charges			0.0
Goodwill, beginning balance		103.7
Disposition	[1]	(3.5)
Foreign exchange and other adjustments		(0.1)
Goodwill, ending balance		100.1
Capital Markets - Compliance and Communications Management
Goodwill [Line Items]
Goodwill, Gross			253.1
Accumulated impairment charges			0.0
Goodwill, beginning balance		253.1
Disposition	[1]	0.0
Foreign exchange and other adjustments		(0.4)
Goodwill, ending balance		252.7
Investment Companies - Software Solutions
Goodwill [Line Items]
Goodwill, Gross			53.2
Accumulated impairment charges			0.0
Goodwill, beginning balance		53.2
Disposition	[1]	0.0
Foreign exchange and other adjustments		(0.2)
Goodwill, ending balance		53.0
Investment Companies - Compliance and Communications Management
Goodwill [Line Items]
Goodwill, Gross			40.6
Accumulated impairment charges			$ (40.6)
Goodwill, beginning balance		0.0
Disposition	[1]	0.0
Foreign exchange and other adjustments		0.0
Goodwill, ending balance		$ 0.0

[1] $3.5 million of CM-SS goodwill was attributed to EOL and included in the disposition in the fourth quarter of 2022.