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Acquisitions/Dispositions (Pro-Forma Information) (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Business Combinations [Abstract] |  |  |
Revenue | $ 15,174 | $ 14,440 | $ 13,724
Income from continuing operations | 1,680 | 1,516 | 1,787
Net income attributable to the Company | $ 1,660 | $ 1,498 | $ 1,759
Basic net income per share: |  |  |
Basic net income per share - Continuing operations (in dollars per share) | $ 3.28 | $ 2.92 | $ 3.39
Basic net income per share - Net income attributable to the Company (in dollars per share) | 3.28 | 2.92 | 3.39
Diluted net income per share: |  |  |
Diluted net income per share - Continuing operations (in dollars per share) | 3.25 | 2.88 | 3.36
Diluted net income per share - Net income attributable to the Company (in dollars per share) | $ 3.25 | $ 2.89 | $ 3.36
Business Acquisition [Line Items] |  |  |
Revenue related to acquisitions |  | $ 156 | $ 25
Net operating income related to acquisitions |  | 19 | $ 4
Acquisition related costs | $ 7 | $ 3 |
Current Fiscal Period Acquisitions |  |  |
Business Acquisition [Line Items] |  |  |
Revenue related to acquisitions | 120 |  |
Net operating income related to acquisitions | $ 2 |  |

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