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Equity Method Investments in Affiliates - Additional Information (Details) shares in Thousands, $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2024 USD ($) | Dec. 31, 2022 USD ($) shares | Dec. 31, 2024 USD ($) yr affiliate | Dec. 31, 2023 USD ($) affiliate | Dec. 31, 2022 USD ($)
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Number of affiliates accounted for under the equity method | affiliate |  |  | 22 | 22 |
BPEA Transaction gain |  | $ 641.9 |  |  |
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 |  |  | $ 29.0 | $ 48.3 | $ 49.1
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
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 |  |
Intangible future amortization expense in 2029 |  |  | $ 15.0 |  |
Equity Method Investee |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Impairment expense | $ 39.9 |  |  | 9.6 |
Equity Method Investee | Growth rate period |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Measurement input | yr |  |  | 10 |  |
Equity Method Investee | Growth rate |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Measurement input |  |  | (0.025) |  |
Equity Method Investee | Long-term growth rate |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Measurement input |  |  | 0.03 |  |
Equity Method Investee | Discount rates, asset based fees |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Measurement input |  |  | 0.12 |  |
Equity Method Investee | Discount rates, performance based fees |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Measurement input |  |  | 0.20 |  |
Equity Method Investee | Market participant tax rates |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Measurement input |  |  | 0.21 |  |
Equity Method Investee | Acquired Client Relationships |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Intangible amortization expense |  |  | $ 90.1 | $ 86.0 | $ 109.1
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Intangible future amortization expense in 2025 |  |  | 75.0 |  |
Intangible future amortization expense in 2026 |  |  | 70.0 |  |
Intangible future amortization expense in 2027 |  |  | 70.0 |  |
Intangible future amortization expense in 2028 |  |  | 60.0 |  |
Intangible future amortization expense in 2029 |  |  | $ 45.0 |  |

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