Condensed Consolidated Statements of Changes in Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Accumulated other comprehensive income (loss)	Consolidated Entity Excluding Consolidated Funds Total stockholders’ equity (deficit)	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 Funds
Beginning balance (in shares) at Dec. 31, 2023				41.4
Beginning balance at Dec. 31, 2023		$ (6.7)	$ 40.2	$ 0.0	$ 0.0	$ 46.9	$ (6.7)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock (in shares)				0.3
Issuance of common stock			0.1		0.1
Repurchases of common stock (in shares)				(4.4)
Repurchase of common stock			(95.7)		(0.4)	(95.3)
Equity-based compensation			0.6		0.6
Foreign currency translation adjustment, net of tax	$ 0.8		0.8				0.8
Amortization related to derivatives securities, net of tax			2.0				2.0
Withholding tax related to stock option exercise and restricted stock vesting	(7.2)		(7.2)		(0.3)	(6.9)
Dividends			(1.2)			(1.2)
Net income	42.5		42.5			42.5
Ending balance (in shares) at Sep. 30, 2024				37.3
Ending balance at Sep. 30, 2024		(3.9)	(17.9)	$ 0.0	0.0	(14.0)	(3.9)
Beginning balance at Dec. 31, 2023								$ 9.3
Increase (Decrease) in redeemable non-controlling interest in consolidated Funds
Net income attributable to redeemable non-controlling interests in consolidated Funds	3.7							3.7
Capital contributions	1.1							1.1
Ending balance at Sep. 30, 2024								14.1
Beginning balance at Dec. 31, 2023	49.5
Increase (Decrease) in total equity and redeemable non-controlling interest in consolidated Funds
Issuance of common stock	0.1
Repurchase of common stock	(95.7)
Capital contributions	1.1							1.1
Equity-based compensation	0.6
Foreign currency translation adjustment, net of tax	0.8
Amortization related to derivative securities, net of tax	2.0
Withholding tax related to stock option exercise and restricted stock vesting	(7.2)		(7.2)		(0.3)	(6.9)
Dividends	(1.2)
Net income	46.2
Ending balance at Sep. 30, 2024	(3.8)
Beginning balance (in shares) at Jun. 30, 2024				37.1
Beginning balance at Jun. 30, 2024		(5.4)	(30.8)	$ 0.0	0.0	(25.4)	(5.4)
Increase (Decrease) in Stockholders' Equity
Issuance of common stock (in shares)				0.2
Issuance of common stock			0.1		0.1
Equity-based compensation			0.2		0.2
Foreign currency translation adjustment, net of tax	0.8		0.8				0.8
Amortization related to derivatives securities, net of tax			0.7				0.7
Withholding tax related to stock option exercise and restricted stock vesting	(5.4)		(5.4)		(0.3)	(5.1)
Dividends			(0.4)			(0.4)
Net income	16.9		16.9			16.9
Ending balance (in shares) at Sep. 30, 2024				37.3
Ending balance at Sep. 30, 2024		(3.9)	(17.9)	$ 0.0	0.0	(14.0)	(3.9)
Beginning balance at Jun. 30, 2024								12.0
Increase (Decrease) in redeemable non-controlling interest in consolidated Funds
Net income attributable to redeemable non-controlling interests in consolidated Funds	2.1							2.1
Ending balance at Sep. 30, 2024								14.1
Beginning balance at Jun. 30, 2024	(18.8)
Increase (Decrease) in total equity and redeemable non-controlling interest in consolidated Funds
Issuance of common stock	0.1
Equity-based compensation	0.2
Foreign currency translation adjustment, net of tax	0.8
Amortization related to derivative securities, net of tax	0.7
Withholding tax related to stock option exercise and restricted stock vesting	(5.4)		(5.4)		(0.3)	(5.1)
Dividends	(0.4)
Net income	19.0
Ending balance at Sep. 30, 2024	(3.8)
Beginning balance (in shares) at Dec. 31, 2024				37.5
Beginning balance at Dec. 31, 2024		(4.4)	20.0	$ 0.0	0.0	24.4	(4.4)
Increase (Decrease) in Stockholders' Equity
Repurchases of common stock (in shares)				(1.8)
Repurchase of common stock			(48.4)		(1.7)	(46.7)
Equity-based compensation			1.9		1.9
Foreign currency translation adjustment, net of tax	0.7		0.7				0.7
Amortization related to derivatives securities, net of tax			2.2				2.2
Withholding tax related to stock option exercise and restricted stock vesting	(0.2)		(0.2)		(0.2)
Dividends			(1.1)			(1.1)
Net income	45.3		45.3			45.3
Ending balance (in shares) at Sep. 30, 2025				35.7
Ending balance at Sep. 30, 2025		(1.5)	20.4	$ 0.0	0.0	21.9	(1.5)
Beginning balance at Dec. 31, 2024								67.1
Increase (Decrease) in redeemable non-controlling interest in consolidated Funds
Net income attributable to redeemable non-controlling interests in consolidated Funds	24.6							24.6
Capital contributions	142.1							142.1
Net deconsolidation of Funds								(142.9)
Ending balance at Sep. 30, 2025								90.9
Beginning balance at Dec. 31, 2024	87.1
Increase (Decrease) in total equity and redeemable non-controlling interest in consolidated Funds
Repurchase of common stock	(48.4)
Capital contributions	142.1							142.1
Equity-based compensation	1.9
Foreign currency translation adjustment, net of tax	0.7
Amortization related to derivative securities, net of tax	2.2
Withholding tax related to stock option exercise and restricted stock vesting	(0.2)		(0.2)		(0.2)
Net deconsolidation of Funds	(142.9)
Dividends	(1.1)
Net income	69.9
Ending balance at Sep. 30, 2025	111.3
Beginning balance (in shares) at Jun. 30, 2025				35.8
Beginning balance at Jun. 30, 2025		(2.1)	9.2	$ 0.0	0.0	11.3	(2.1)
Increase (Decrease) in Stockholders' Equity
Repurchases of common stock (in shares)				(0.1)
Repurchase of common stock			(5.0)		(0.8)	(4.2)
Equity-based compensation			0.8		0.8
Foreign currency translation adjustment, net of tax	(0.2)		(0.2)				(0.2)
Amortization related to derivatives securities, net of tax			0.8				0.8
Dividends			(0.3)			(0.3)
Net income	15.1		15.1			15.1
Ending balance (in shares) at Sep. 30, 2025				35.7
Ending balance at Sep. 30, 2025		$ (1.5)	$ 20.4	$ 0.0	$ 0.0	$ 21.9	$ (1.5)
Beginning balance at Jun. 30, 2025								77.7
Increase (Decrease) in redeemable non-controlling interest in consolidated Funds
Net income attributable to redeemable non-controlling interests in consolidated Funds	11.9							11.9
Capital contributions	144.2							144.2
Net deconsolidation of Funds								(142.9)
Ending balance at Sep. 30, 2025								90.9
Beginning balance at Jun. 30, 2025	86.9
Increase (Decrease) in total equity and redeemable non-controlling interest in consolidated Funds
Repurchase of common stock	(5.0)
Capital contributions	144.2							$ 144.2
Equity-based compensation	0.8
Foreign currency translation adjustment, net of tax	(0.2)
Amortization related to derivative securities, net of tax	0.8
Net deconsolidation of Funds	(142.9)
Dividends	(0.3)
Net income	27.0
Ending balance at Sep. 30, 2025	$ 111.3