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Acquisitions (Allocation Of Acquisition Costs) (Details) - USD ($) $ in Millions | 6 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Dec. 31, 2017 | Dec. 31, 2016
Business Acquisition [Line Items] |  |  |  |
Cash | $ 160 | $ 420 |  |
Estimated fair value of deferred/contingent consideration | 32 | 90 |  |
Total Consideration | 192 | 510 |  |
Allocation of purchase price: |  |  |  |
Goodwill | 9,177 | $ 8,821 | $ 9,089 | $ 8,369
Current Fiscal Period Acquisitions |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Cash | 160 |  |  |
Estimated fair value of deferred/contingent consideration | 32 |  |  |
Total Consideration | 192 |  |  |
Allocation of purchase price: |  |  |  |
Cash and cash equivalents | 16 |  |  |
Accounts receivable, net | 12 |  |  |
Property, plant, and equipment | 3 |  |  |
Other intangible assets | 73 |  |  |
Goodwill | 116 |  |  |
Total assets acquired | 220 |  |  |
Current liabilities | 10 |  |  |
Other liabilities | 18 |  |  |
Total liabilities assumed | 28 |  |  |
Net assets acquired | $ 192 |  |  |

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