Investments - Schedule of Investments (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Investments [Abstract]
Accrued performance allocations	$ 6,956.3	$ 7,053.5
Principal equity method investments, excluding performance allocations	2,942.5	3,292.3
Principal investments in CLOs	380.7	378.9
Other investments	235.9	212.0
Total	$ 10,515.4	$ 10,936.7

Sum of the carrying amounts as of the balance sheet date of all investments.

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