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v3.25.1

Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Financial instruments owned: |  |
Exchange traded equity securities | $ 22 | $ 19
Fair Value, Measurements, Recurring |  |
Financial instruments owned: |  |
Exchange traded equity securities | 11 | 7
Mutual funds | 191 | 194
Money market funds | 355 | 353
Total assets measured at fair value | 557 | 637
Fiduciary Assets: |  |
Total fiduciary assets measured at fair value | 59 | 76
Liabilities: |  |
Contingent purchase consideration liabilities | 160 | 161
Total liabilities measured at fair value | 160 | 161
Fair Value, Measurements, Recurring | Other Assets |  |
Financial instruments owned: |  |
Unit investment trust | 0 | 83
Identical Assets (Level 1) | Fair Value, Measurements, Recurring |  |
Financial instruments owned: |  |
Exchange traded equity securities | 11 | 7
Mutual funds | 191 | 194
Money market funds | 355 | 353
Total assets measured at fair value | 557 | 554
Fiduciary Assets: |  |
Total fiduciary assets measured at fair value | 59 | 76
Liabilities: |  |
Contingent purchase consideration liabilities | 0 | 0
Total liabilities measured at fair value | 0 | 0
Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Other Assets |  |
Financial instruments owned: |  |
Unit investment trust | 0 | 0
Observable Inputs (Level 2) | Fair Value, Measurements, Recurring |  |
Financial instruments owned: |  |
Exchange traded equity securities | 0 | 0
Mutual funds | 0 | 0
Money market funds | 0 | 0
Total assets measured at fair value | 0 | 83
Fiduciary Assets: |  |
Total fiduciary assets measured at fair value | 0 | 0
Liabilities: |  |
Contingent purchase consideration liabilities | 0 | 0
Total liabilities measured at fair value | 0 | 0
Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Other Assets |  |
Financial instruments owned: |  |
Unit investment trust | 0 | 83
Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring |  |
Financial instruments owned: |  |
Exchange traded equity securities | 0 | 0
Mutual funds | 0 | 0
Money market funds | 0 | 0
Total assets measured at fair value | 0 | 0
Fiduciary Assets: |  |
Total fiduciary assets measured at fair value | 0 | 0
Liabilities: |  |
Contingent purchase consideration liabilities | 160 | 161
Total liabilities measured at fair value | 160 | 161
Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Other Assets |  |
Financial instruments owned: |  |
Unit investment trust | 0 | 0
Money market funds | Fair Value, Measurements, Recurring |  |
Fiduciary Assets: |  |
Total fiduciary assets measured at fair value | 59 | 76
Money market funds | Identical Assets (Level 1) | Fair Value, Measurements, Recurring |  |
Fiduciary Assets: |  |
Total fiduciary assets measured at fair value | 59 | 76
Money market funds | Observable Inputs (Level 2) | Fair Value, Measurements, Recurring |  |
Fiduciary Assets: |  |
Total fiduciary assets measured at fair value | 0 | 0
Money market funds | Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring |  |
Fiduciary Assets: |  |
Total fiduciary assets measured at fair value | $ 0 | $ 0

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