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Equity Method Investments in Affiliates - Additional Information (Details) shares in Thousands, $ in Millions | 3 Months Ended | 5 Months Ended | 12 Months Ended
--- | --- | --- | ---
Dec. 31, 2022 USD ($) yr affiliate shares | Feb. 15, 2023 shares | Dec. 31, 2022 USD ($) yr affiliate | Dec. 31, 2021 USD ($) yr affiliate | Dec. 31, 2020 USD ($)
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Number of affiliates accounted for under the equity method | affiliate | 20 |  | 20 | 21 |
BPEA Transaction gain (Note 10) | $ 641.9 |  | $ 641.9 | $ 0.0 | $ 0.0
EQT AB (“EQT”) | Subsequent Event |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Equity interests issued, shares (in shares) | shares |  | 17,400 |  |  |
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 |  |  | 49.1 | 35.7 |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Intangible future amortization expense in 2023 | $ 50.0 |  | 50.0 |  |
Intangible future amortization expense in 2024 | 35.0 |  | 35.0 |  |
Intangible future amortization expense in 2025 | 30.0 |  | 30.0 |  |
Intangible future amortization expense in 2026 | 30.0 |  | 30.0 |  |
Intangible future amortization expense in 2027 | $ 30.0 |  | 30.0 |  |
Equity Method Investee |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Impairment expense |  |  | $ 50.0 | $ 52.0 |
Equity Method Investee | Growth rate period |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Measurement input | yr | 5 |  | 5 | 5 |
Equity Method Investee | Growth rate |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Measurement input | 0.02 |  | 0.02 | 0.003 |
Equity Method Investee | Long-term growth rate |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Measurement input | 0.05 |  | 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 | 0.11 |
Equity Method Investee | Discount rates, performance based fees |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Measurement input | 0.20 |  | 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 | 0.25 |
Equity Method Investee | Acquired Client Relationships |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Intangible amortization expense |  |  | $ 109.1 | $ 123.0 | $ 147.0
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Intangible future amortization expense in 2023 | $ 85.0 |  | 85.0 |  |
Intangible future amortization expense in 2024 | 55.0 |  | 55.0 |  |
Intangible future amortization expense in 2025 | 50.0 |  | 50.0 |  |
Intangible future amortization expense in 2026 | 45.0 |  | 45.0 |  |
Intangible future amortization expense in 2027 | $ 45.0 |  | $ 45.0 |  |

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