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Equity Method Investments in Affiliates - Additional Information (Details) shares in Thousands, $ in Millions |  | 3 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 16, 2022 USD ($) shares | Mar. 31, 2022 USD ($) affiliate | Mar. 31, 2021 USD ($) affiliate | Dec. 31, 2021 USD ($) | Dec. 31, 2016 USD ($)
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Number of affiliates accounted for under the equity method | affiliate |  | 21 | 19 |  |
Equity method investments |  | $ 105.3 |  | $ 111.4 |
Baring Private Equity Asia (“BPEA”) |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Equity method investments |  | 138.0 |  |  | $ 187.5
Baring Private Equity Asia (“BPEA”) | EQT AB (“EQT”) |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Expected cash proceeds | $ 240.0 |  |  |  |
Expected equity interest 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] |  |  |  |  |
Amortization of Intangible Assets |  | 12.3 |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Finite-lived intangible, future amortization expense, remainder of fiscal year |  | 40.0 |  |  |
Finite-lived intangible, future amortization expense in year one |  | 50.0 |  |  |
Finite-lived intangible, future amortization expense in year two |  | 35.0 |  |  |
Finite-lived intangible, future amortization expense in year three |  | 35.0 |  |  |
Finite-lived intangible, future amortization expense in year four |  | 35.0 |  |  |
Finite-lived intangible, future amortization expense in year five |  | 35.0 |  |  |
Equity Method Investee |  |  |  |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Total contingent payments |  | 83.3 |  |  |
Equity Method Investee | Acquired Client Relationships |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Amortization of Intangible Assets |  | 23.3 | $ 35.2 |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |  |  |
Finite-lived intangible, future amortization expense, remainder of fiscal year |  | 70.0 |  |  |
Finite-lived intangible, future amortization expense in year one |  | 85.0 |  |  |
Finite-lived intangible, future amortization expense in year two |  | 50.0 |  |  |
Finite-lived intangible, future amortization expense in year three |  | 50.0 |  |  |
Finite-lived intangible, future amortization expense in year four |  | 45.0 |  |  |
Finite-lived intangible, future amortization expense in year five |  | $ 40.0 |  |  |

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