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Per Share Data (Basic and Diluted EPS Calculation Continuing Operations) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017
Earnings Per Share [Abstract] |  |  |  |
Net income before non-controlling interests | $ 279 | $ 397 | $ 1,511 | $ 1,482
Less: Net income attributable to non-controlling interests | 3 | 4 | 14 | 19
Net income attributable to the Company | $ 276 | $ 393 | $ 1,497 | $ 1,463
Basic weighted average common shares outstanding (in shares) | 504 | 512 | 506 | 514
Dilutive effect of potentially issuable common shares (in shares) | 6 | 7 | 6 | 6
Diluted weighted average common shares outstanding (in shares) | 510 | 519 | 512 | 520
Average stock price used to calculate common stock equivalents (in dollars per share) | $ 84.68 | $ 79.35 | $ 83.05 | $ 75.36

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