Condensed Consolidated Statements of Changes in Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Consolidated Entity Excluding Consolidated Funds Common Stock	Consolidated Entity Excluding Consolidated Funds Additional paid-in capital	Consolidated Entity Excluding Consolidated Funds Retained earnings (deficit)	Consolidated Entity Excluding Consolidated Funds Accumulated other comprehensive income (loss)	Consolidated Entity Excluding Consolidated Funds Total stockholders’ equity	Consolidated Entity Excluding Consolidated Funds Non- controlling interests	Consolidated Funds Non- controlling interests
Beginning balance (in shares) at Dec. 31, 2020		79.4
Beginning balance at Dec. 31, 2020	$ 384.4	$ 0.1	$ 492.4	$ (176.5)	$ (13.6)	$ 302.4	$ 1.7	$ 80.3
Increase (Decrease) in Stockholders' Equity
Issuance of common stock (in shares)		0.4
Issuance of common stock	0.2		0.2			0.2
Capital contributions	33.5						3.8	29.7
Equity-based compensation	1.3		1.3			1.3
Foreign currency translation adjustment	0.3				0.3	0.3
Amortization related to derivatives securities, net of tax	1.8				1.8	1.8
Withholding tax related to stock option exercise	(8.9)		(8.9)			(8.9)
Other changes in non-controlling interests	(5.5)						(5.5)
Net de-consolidation of Funds	(178.0)							(178.0)
Dividends	(2.3)			(2.3)		(2.3)
Net income	857.2			789.2		789.2		68.0
Ending balance (in shares) at Sep. 30, 2021		79.8
Ending balance at Sep. 30, 2021	1,084.0	$ 0.1	485.0	610.4	(11.5)	1,084.0	0.0	0.0
Beginning balance (in shares) at Jun. 30, 2021		79.4
Beginning balance at Jun. 30, 2021	863.9	$ 0.1	493.4	381.6	(11.2)	863.9	0.0	0.0
Increase (Decrease) in Stockholders' Equity
Issuance of common stock (in shares)		0.4
Issuance of common stock	0.1		0.1			0.1
Equity-based compensation	0.4		0.4			0.4
Foreign currency translation adjustment	(0.9)				(0.9)	(0.9)
Amortization related to derivatives securities, net of tax	0.6				0.6	0.6
Withholding tax related to stock option exercise	(8.9)		(8.9)			(8.9)
Dividends	(0.7)			(0.7)		(0.7)
Net income	229.5			229.5		229.5		0.0
Ending balance (in shares) at Sep. 30, 2021		79.8
Ending balance at Sep. 30, 2021	1,084.0	$ 0.1	485.0	610.4	(11.5)	1,084.0	0.0	0.0
Beginning balance (in shares) at Dec. 31, 2021		45.4
Beginning balance at Dec. 31, 2021	(17.6)	$ 0.0	0.0	(6.8)	(10.8)	(17.6)	0.0	0.0
Increase (Decrease) in Stockholders' Equity
Issuance of common stock (in shares)		0.2
Repurchase of common stock (in shares)		(4.2)
Repurchase of common stock	(103.2)			(103.2)		(103.2)
Equity-based compensation	1.8		1.8			1.8
Foreign currency translation adjustment	(5.6)				(5.6)	(5.6)
Amortization related to derivatives securities, net of tax	2.8				2.8	2.8
Withholding tax related to stock option exercise	(2.3)		(0.9)	(1.4)		(2.3)
Dividends	(1.2)			(1.2)		(1.2)
Net income	70.2			70.2		70.2
Ending balance (in shares) at Sep. 30, 2022		41.4
Ending balance at Sep. 30, 2022	(55.1)	$ 0.0	0.9	(42.4)	(13.6)	(55.1)	0.0	0.0
Beginning balance (in shares) at Jun. 30, 2022		41.4
Beginning balance at Jun. 30, 2022	(71.0)	$ 0.0	0.5	(59.8)	(11.7)	(71.0)	0.0	0.0
Increase (Decrease) in Stockholders' Equity
Equity-based compensation	0.4		0.4			0.4
Foreign currency translation adjustment	(2.5)				(2.5)	(2.5)
Amortization related to derivatives securities, net of tax	0.6				0.6	0.6
Dividends	(0.4)			(0.4)		(0.4)
Net income	17.8			17.8		17.8
Ending balance (in shares) at Sep. 30, 2022		41.4
Ending balance at Sep. 30, 2022	$ (55.1)	$ 0.0	$ 0.9	$ (42.4)	$ (13.6)	$ (55.1)	$ 0.0	$ 0.0