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Other Investments - Investments Measured at NAV as a Practical Expedient (Details) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2023 | Dec. 31, 2022
NAV of investments at fair value |  |
Unfunded Commitments | $ 154.3 | $ 158.3
Life of funds (generally up to) | 15 years |
Private equity funds |  |
NAV of investments at fair value |  |
Unfunded Commitments | $ 154.3 | 158.3
Investments in other strategies |  |
NAV of investments at fair value |  |
Unfunded Commitments | 0.0 | 0.0
Fair Value Measured at NAV |  |
NAV of investments at fair value |  |
Fair Value | 406.6 | 371.2
Fair Value Measured at NAV | Controlling Interest |  |
NAV of investments at fair value |  |
Fair Value | 295.7 | 275.1
Fair Value Measured at NAV | Private equity funds |  |
NAV of investments at fair value |  |
Fair Value | 378.5 | 356.4
Fair Value Measured at NAV | Investments in other strategies |  |
NAV of investments at fair value |  |
Fair Value | $ 28.1 | $ 14.8

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