Investments - Schedule of Investments (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Investment Holdings [Line Items]
Total investments per Condensed Consolidated Balance Sheets	$ 225.7	$ 221.9
Consolidated Funds
Investment Holdings [Line Items]
Investments	170.5	154.0
Total investments per Condensed Consolidated Balance Sheets	170.5	154.0
Consolidated Entity Excluding Consolidated Funds
Investment Holdings [Line Items]
Total investments per Condensed Consolidated Balance Sheets	55.2	67.9
Consolidated Entity Excluding Consolidated Funds | Other investments
Investment Holdings [Line Items]
Investments	19.3	19.4
Consolidated Entity Excluding Consolidated Funds | Investments related to long-term incentive compensation plans
Investment Holdings [Line Items]
Investments	$ 35.9	$ 48.5