IPO and Private Placement - Narrative (Details) $ / shares in Units, $ in Millions	Jul. 06, 2020 USD ($) $ / shares shares	Jun. 23, 2020 shares	Sep. 30, 2020 $ / shares shares	Dec. 31, 2019 $ / shares shares
Class of Stock [Line Items]
Stock issued (shares)	108,506,312
Common stock, par value (USD per share) | $ / shares			$ 0.0001	$ 0.0001
Gross proceeds from sale of stock | $	$ 2,381.0
Common stock authorized (shares)		2,000,000,000	2,000,000,000	2,000,000,000
Preferred stock authorized (shares)		25,000,000
Stock split ratio		314,494.968
IPO
Class of Stock [Line Items]
Stock issued (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)	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]
Gross proceeds from sale of stock | $	$ 200.0
Private Placement | Subsidiary of Black Knight
Class of Stock [Line Items]
Gross proceeds from sale of stock | $	100.0
Private Placement | Affiliate of CC Capital
Class of Stock [Line Items]
Gross proceeds from sale of stock | $	$ 100.0