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Equity Method Investments in Affiliates - Additional Information (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 USD ($) affiliate | Mar. 31, 2023 USD ($) | Dec. 31, 2023 affiliate
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |
Number of affiliates accounted for under the equity method | affiliate | 22 |  | 22
Acquired Client Relationships |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Amortization of Intangible Assets | $ 7.3 |  |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |
Finite-lived intangible, future amortization expense, remainder of fiscal year | 22.0 |  |
Finite-lived intangible, future amortization expense in year five | 13.0 |  |
Equity Method Investee | Acquired Client Relationships |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Amortization of Intangible Assets | 20.8 | $ 20.9 |
Estimated Future Amortization Expense of Finite-Lived Intangibles |  |  |
Finite-lived intangible, future amortization expense, remainder of fiscal year | 62.0 |  |
Finite-lived intangible, future amortization expense in year one | 77.0 |  |
Finite-lived intangible, future amortization expense in year two | 73.0 |  |
Finite-lived intangible, future amortization expense in year three | 73.0 |  |
Finite-lived intangible, future amortization expense in year four | 65.0 |  |
Finite-lived intangible, future amortization expense in year five | $ 50.0 |  |

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