Condensed Consolidated Statements of Equity - USD ($) $ in Millions	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive loss	Treasury stock	Redeemable noncontrolling interests	Total
Beginning balance at Dec. 31, 2020		$ 2,053.7	$ 757.4	$ (38.8)	$ (144.6)	$ 578.0	$ 2,627.7
Beginning balance (shares) at Dec. 31, 2020	160,100,000				3,100,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Fair value adjustment to redeemable noncontrolling interests		(392.3)				392.3	(392.3)
Grant of restricted shares of common stock		(29.2)			$ 29.2
Grant of restricted shares of common stock (in shares)					(600,000)
Forfeitures of restricted shares of common stock		1.6			$ (1.6)
Tax withholding payments for restricted share vesting		(24.4)					(24.4)
Tax withholding payments for restricted share vesting (shares)	(100,000)
Vesting of restricted shares granted from treasury stock		11.4			$ (11.4)
Vesting of restricted shares granted from treasury stock (in shares)					200,000
Equity based compensation expense		32.4					32.4
Net earnings (losses)			147.2			(23.2)	147.2
Equity-based compensation expense of unconsolidated affiliates			2.0				2.0
Purchases of treasury stock					$ (146.7)		$ (146.7)
Purchases of treasury stock (in shares)					2,000,000.0		(2,000,000.0)
Foreign currency translation adjustment				(0.4)			$ (0.4)
Unrealized gains on interest rate swaps, net				12.0			12.0
Other comprehensive gains (loss) on investments in unconsolidated affiliates				(4.5)			(4.5)
Ending balance at Sep. 30, 2021		1,653.2	906.6	(31.7)	$ (275.1)	947.1	2,253.0
Ending balance (shares) at Sep. 30, 2021	160,000,000.0				4,700,000
Beginning balance at Dec. 31, 2020		2,053.7	757.4	(38.8)	$ (144.6)	578.0	2,627.7
Beginning balance (shares) at Dec. 31, 2020	160,100,000				3,100,000
Ending balance at Dec. 31, 2021		1,410.9	968.2	(17.5)	$ (271.2)	1,188.8	2,090.4
Ending balance (shares) at Dec. 31, 2021	160,000,000.0				4,700,000
Beginning balance at Jun. 30, 2021		2,021.0	852.4	(32.6)	$ (176.6)	578.0	2,664.2
Beginning balance (shares) at Jun. 30, 2021	160,000,000.0				3,400,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Fair value adjustment to redeemable noncontrolling interests		(376.2)				376.2	(376.2)
Grant of restricted shares of common stock		(2.6)			$ 2.6
Grant of restricted shares of common stock (in shares)					(100,000)
Forfeitures of restricted shares of common stock		1.1			$ (1.1)
Equity based compensation expense		9.9					9.9
Net earnings (losses)			53.4			(7.1)	53.4
Equity-based compensation expense of unconsolidated affiliates			0.8				0.8
Purchases of treasury stock					$ (100.0)		$ (100.0)
Purchases of treasury stock (in shares)					1,400,000		(1,400,000)
Unrealized gains on interest rate swaps, net				3.8			$ 3.8
Other comprehensive gains (loss) on investments in unconsolidated affiliates				(2.9)			(2.9)
Ending balance at Sep. 30, 2021		1,653.2	906.6	(31.7)	$ (275.1)	947.1	2,253.0
Ending balance (shares) at Sep. 30, 2021	160,000,000.0				4,700,000
Beginning balance at Dec. 31, 2021		1,410.9	968.2	(17.5)	$ (271.2)	1,188.8	2,090.4
Beginning balance (shares) at Dec. 31, 2021	160,000,000.0				4,700,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Fair value adjustment to redeemable noncontrolling interests		(12.5)				12.5	(12.5)
Acquisition of remaining redeemable noncontrolling interests in Optimal Blue Holdco, LLC						(1,156.0)
Grant of restricted shares of common stock		(51.8)			$ 51.8
Grant of restricted shares of common stock (in shares)					(900,000)
Forfeitures of restricted shares of common stock		2.0			$ (2.0)
Tax withholding payments for restricted share vesting		(11.2)					(11.2)
Vesting of restricted shares granted from treasury stock		8.9			$ (8.9)
Vesting of restricted shares granted from treasury stock (in shares)					200,000
Equity based compensation expense		37.2					37.2
Net earnings (losses)			434.9			(2.5)	434.9
Equity-based compensation expense of unconsolidated affiliates			(4.3)				$ (4.3)
Purchases of treasury stock (in shares)							0
Foreign currency translation adjustment				(1.0)			$ (1.0)
Unrealized gains on interest rate swaps, net				13.6			13.6
Other comprehensive gains (loss) on investments in unconsolidated affiliates				(1.1)			(1.1)
Other		3.1					3.1
Ending balance at Sep. 30, 2022		1,386.6	1,398.8	(6.0)	$ (230.3)	42.8	2,549.1
Ending balance (shares) at Sep. 30, 2022	160,000,000.0				4,000,000.0
Beginning balance at Jun. 30, 2022		1,367.8	1,368.2	(5.5)	$ (230.4)	47.4	2,500.1
Beginning balance (shares) at Jun. 30, 2022	160,000,000.0				4,000,000.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Fair value adjustment to redeemable noncontrolling interests		4.6				(4.6)	4.6
Grant of restricted shares of common stock		(1.0)			$ 1.0
Forfeitures of restricted shares of common stock		0.8			(0.8)
Tax withholding payments for restricted share vesting		(0.2)					(0.2)
Vesting of restricted shares granted from treasury stock		0.1			(0.1)
Equity based compensation expense		13.6					13.6
Net earnings (losses)			30.0				30.0
Equity-based compensation expense of unconsolidated affiliates			0.6				0.6
Foreign currency translation adjustment				(0.4)			(0.4)
Unrealized gains on interest rate swaps, net				1.8			1.8
Other comprehensive gains (loss) on investments in unconsolidated affiliates				(1.9)			(1.9)
Other		0.9					0.9
Ending balance at Sep. 30, 2022		$ 1,386.6	$ 1,398.8	$ (6.0)	$ (230.3)	$ 42.8	$ 2,549.1
Ending balance (shares) at Sep. 30, 2022	160,000,000.0				4,000,000.0