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Acquisitions (Pro-Forma Information) (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016
Business Combinations [Abstract] |  |  |  |
Revenue | $ 3,496 | $ 3,493 | $ 7,011 | $ 6,951
Net income attributable to the Company | $ 502 | $ 470 | $ 1,072 | $ 950
Basic net income per share: |  |  |  |
Basic net income per share attributable to the Company (in dollars per share) | $ 0.98 | $ 0.90 | $ 2.08 | $ 1.82
Diluted net income per share: |  |  |  |
Diluted net income per share attributable to the Company (in dollars per share) | $ 0.96 | $ 0.89 | $ 2.06 | $ 1.81

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