Business Acquisitions - Estimated Useful Lives of Assets Acquired (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Sep. 15, 2020
Acquired Finite-Lived Intangible Assets [Line Items]
Property and equipment, useful life (in years)	5 years
Acquisitions
Acquired Finite-Lived Intangible Assets [Line Items]
Software	$ 34.9
Other intangible assets	80.0
Acquisitions | Client relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Other intangible assets	76.3
Optimal Blue Holdco, LLC
Acquired Finite-Lived Intangible Assets [Line Items]
Software		$ 79.7
Other intangible assets		$ 610.8
Optimal Blue Holdco, LLC | Client relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Other intangible assets	$ 602.5