Basis of Presentation - Narrative (Details) $ / shares in Units, $ in Millions		9 Months Ended
	Jul. 06, 2020 USD ($) $ / shares shares	Sep. 30, 2020 segment $ / shares	Dec. 31, 2019 $ / shares
Class of Stock [Line Items]
Stock issued (shares) | shares	108,506,312
Common stock, par value (USD per share) | $ / shares		$ 0.0001	$ 0.0001
Consideration received on transaction	$ 2,381.0
Number of reportable segments | segment		2
IPO
Class of Stock [Line Items]
Stock issued (shares) | shares	90,047,612
Common stock, par value (USD per share) | $ / shares	$ 0.0001
Offering price (USD per share) | $ / shares	$ 22.00
Private Placement
Class of Stock [Line Items]
Stock issued (shares) | shares	18,458,700
Issuance price per share relative to IPO price per share (as a percent)	98.50%
Private Placement | Subsidiary of Cannae Holdings
Class of Stock [Line Items]
Consideration received on transaction	$ 200.0
Private Placement | Subsidiary of Black Knight
Class of Stock [Line Items]
Consideration received on transaction	100.0
Private Placement | Affiliate of CC Capital
Class of Stock [Line Items]
Consideration received on transaction	$ 100.0