Investments - Schedule of Investment Components (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Investment Holdings [Line Items]
Total investments per Condensed Consolidated Balance Sheets	$ 56.7	$ 50.3
Consolidated Funds
Investment Holdings [Line Items]
Investments at fair value	9.3	1.9
Total investments per Condensed Consolidated Balance Sheets	9.3	1.9
Consolidated Entity Excluding Consolidated Funds
Investment Holdings [Line Items]
Total investments per Condensed Consolidated Balance Sheets	47.4	48.4
Other investments | Consolidated Entity Excluding Consolidated Funds
Investment Holdings [Line Items]
Investments at fair value	4.4	8.4
Investments related to long-term incentive compensation plans | Consolidated Entity Excluding Consolidated Funds
Investment Holdings [Line Items]
Investments at fair value	$ 43.0	$ 40.0