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Acquisitions and Dispositions (Allocation Of Acquisition Costs) (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023 | Dec. 31, 2022
Business Acquisition [Line Items] |  |  |  |
Cash | $ 308 | $ 11 |  |
Estimated fair value of deferred/contingent purchase consideration | 51 | 4 |  |
Total consideration | 359 | 15 |  |
Allocation of purchase price: |  |  |  |
Goodwill | 17,314 | $ 16,300 | $ 17,231 | $ 16,251
Current Fiscal Period Acquisitions |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Cash | 308 |  |  |
Estimated fair value of deferred/contingent purchase consideration | 51 |  |  |
Total consideration | 359 |  |  |
Allocation of purchase price: |  |  |  |
Cash and cash equivalents | 2 |  |  |
Cash and cash equivalents held in a fiduciary capacity | 5 |  |  |
Net receivables | 35 |  |  |
Goodwill | 216 |  |  |
Other intangible assets | 115 |  |  |
Fixed assets, net | 3 |  |  |
Right of use assets | 1 |  |  |
Other assets | 2 |  |  |
Total assets acquired | 379 |  |  |
Current liabilities | 6 |  |  |
Fiduciary liabilities | 5 |  |  |
Other liabilities | 9 |  |  |
Total liabilities assumed | 20 |  |  |
Net assets acquired | $ 359 |  |  |

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