Accounts Payable and Accrued Expenses (Details) - Consolidated Entity Excluding Consolidated Funds - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Accounts Payable And Accrued Expenses [Line Items]
Accounts payable	$ 5.0	$ 6.7
Accrued expenses	23.4	17.8
Accrued interest payable	6.8	6.8
Total accounts payable and accrued expenses	$ 35.2	$ 31.3