Investments - Components of Accrued Giveback Obligations (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Accrued giveback obligations	$ (44.0)	$ (40.9)
Global Private Equity
Segment Reporting Information [Line Items]
Accrued giveback obligations	(18.4)	(18.4)
Global Credit
Segment Reporting Information [Line Items]
Accrued giveback obligations	$ (25.6)	$ (22.5)