Goodwill (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2020
Goodwill [Roll Forward]
Beginning balance		$ 2,361.4
Goodwill acquired		25.3
Compass Analytics acquisition adjustment	$ 0.2	(0.9)
Ending balance	2,385.8	2,385.8
Operating Segments \| Software Solutions
Goodwill [Roll Forward]
Beginning balance		2,189.3
Goodwill acquired		0.0
Compass Analytics acquisition adjustment		(0.9)
Ending balance	2,188.4	2,188.4
Operating Segments \| Data and Analytics
Goodwill [Roll Forward]
Beginning balance		172.1
Goodwill acquired		25.3
Compass Analytics acquisition adjustment		0.0
Ending balance	197.4	197.4
Corporate and Other
Goodwill [Roll Forward]
Beginning balance		0.0
Goodwill acquired		0.0
Compass Analytics acquisition adjustment		0.0
Ending balance	$ 0.0	$ 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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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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