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Acquisitions and Dispositions (Allocation Of Acquisition Costs) (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022 | Dec. 31, 2021
Business Acquisition [Line Items] |  |  |  |
Cash | $ 11 | $ 24 |  |
Estimated fair value of deferred/contingent consideration | 4 | 4 |  |
Total consideration | 15 | 28 |  |
Allocation of purchase price: |  |  |  |
Goodwill | 16,300 | $ 16,254 | $ 16,251 | $ 16,317
Current Fiscal Period Acquisitions |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Cash | 11 |  |  |
Estimated fair value of deferred/contingent consideration | 4 |  |  |
Total consideration | 15 |  |  |
Allocation of purchase price: |  |  |  |
Net receivables | 2 |  |  |
Goodwill | 11 |  |  |
Other intangible assets | 4 |  |  |
Total assets acquired | 17 |  |  |
Current liabilities | 2 |  |  |
Total liabilities assumed | 2 |  |  |
Net assets acquired | $ 15 |  |  |

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