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Equity Method Investments in Affiliates - Additional Information (Details) shares in Thousands, $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2022 USD ($) yr affiliate shares | Dec. 31, 2023 USD ($) affiliate | Dec. 31, 2022 USD ($) yr affiliate | Dec. 31, 2021 USD ($)
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |
Number of affiliates accounted for under the equity method | affiliate | 20 | 22 | 20 |
BPEA Transaction gain | $ 641.9 | $ 133.1 | $ 641.9 | $ 0.0
Baring Private Equity Asia (“BPEA”) | EQT AB (“EQT”) |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |
Merger agreement, cash proceeds | $ 223.6 |  |  |
Merger agreement, equity interests issuable, number of shares (in shares) | shares | 28,680 |  |  |
Percentage of shares restricted | 0.25 |  |  |
Term of restricted shares | 6 months |  |  |
Acquired Client Relationships |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Intangible amortization expense |  | 48.3 | 49.1 |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |
Intangible future amortization expense in 2024 |  | 30.0 |  |
Intangible future amortization expense in 2025 |  | 25.0 |  |
Intangible future amortization expense in 2026 |  | 25.0 |  |
Intangible future amortization expense in 2027 |  | 25.0 |  |
Intangible future amortization expense in 2028 |  | 25.0 |  |
Equity Method Investee |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |
Impairment expense |  | 9.6 | $ 50.0 |
Equity Method Investee | Growth rate period |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |
Measurement input | yr | 5 |  | 5 |
Equity Method Investee | Growth rate |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |
Measurement input | 0.02 |  | 0.02 |
Equity Method Investee | Long-term growth rate |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |
Measurement input | 0.05 |  | 0.05 |
Equity Method Investee | Discount rates, asset based fees |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |
Measurement input | 0.11 |  | 0.11 |
Equity Method Investee | Discount rates, performance based fees |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |
Measurement input | 0.20 |  | 0.20 |
Equity Method Investee | Market participant tax rates |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |
Measurement input | 0.25 |  | 0.25 |
Equity Method Investee | Acquired Client Relationships |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Intangible amortization expense |  | 86.0 | $ 109.1 | $ 123.0
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |
Intangible future amortization expense in 2024 |  | 65.0 |  |
Intangible future amortization expense in 2025 |  | 62.0 |  |
Intangible future amortization expense in 2026 |  | 55.0 |  |
Intangible future amortization expense in 2027 |  | 55.0 |  |
Intangible future amortization expense in 2028 |  | $ 50.0 |  |

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