Goodwill (Details) $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 2,361.4
Ending balance	3,617.6
Measurement period adjustment	(0.9)
Optima Blue
Goodwill [Roll Forward]
Goodwill acquired	1,210.2
Other Acquisitions
Goodwill [Roll Forward]
Goodwill acquired	46.0
Operating Segments \| Software Solutions
Goodwill [Roll Forward]
Beginning balance	2,189.3
Ending balance	3,420.0
Operating Segments \| Software Solutions \| Optima Blue
Goodwill [Roll Forward]
Goodwill acquired	1,210.2
Operating Segments \| Software Solutions \| Other Acquisitions
Goodwill [Roll Forward]
Goodwill acquired	20.5
Operating Segments \| Data and Analytics
Goodwill [Roll Forward]
Beginning balance	172.1
Ending balance	197.6
Operating Segments \| Data and Analytics \| Optima Blue
Goodwill [Roll Forward]
Goodwill acquired	0.0
Operating Segments \| Data and Analytics \| Other Acquisitions
Goodwill [Roll Forward]
Goodwill acquired	25.5
Corporate and Other
Goodwill [Roll Forward]
Beginning balance	0.0
Ending balance	0.0
Corporate and Other \| Optima Blue
Goodwill [Roll Forward]
Goodwill acquired	0.0
Corporate and Other \| Other Acquisitions
Goodwill [Roll Forward]
Goodwill acquired	$ 0.0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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