Segment Reporting - Expense Adjustments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Equity-based compensation	$ 249.1	$ 154.0	$ 163.1
Right-of-use asset impairment			26.8
Expenses	3,571.7	2,824.7	4,757.1
Total Reportable Segments
Segment Reporting Information [Line Items]
Unrealized performance and fee related performance revenue compensation expense	612.6	(326.2)	1,549.4
Expenses	1,974.6	2,492.4	2,706.4
Reconciling Items
Segment Reporting Information [Line Items]
Equity-based compensation	260.1	161.9	172.9
Acquisition or disposition-related charges and amortization of intangibles and impairment	145.3	187.4	37.7
Tax (expense) benefit associated with certain foreign performance revenues related compensation	(1.0)	2.9	(17.3)
Non-controlling interests and other adjustments to present certain costs on a net basis	148.7	82.7	78.5
Debt extinguishment costs	0.0	0.0	10.2
Right-of-use asset impairment	0.0	0.0	26.8
Other adjustments	11.6	12.4	14.2
Expenses	1,136.8	77.0	1,832.9
Eliminations
Segment Reporting Information [Line Items]
Equity-based compensation	0.0	0.0	0.0
Expenses	$ (40.5)	$ (44.1)	$ (39.5)