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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 | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Earnings Per Share [Abstract] |  |  |  |
Net income before non-controlling interests | $ 344 | $ 536 | $ 1,071 | $ 1,232
Less: Net income attributable to non-controlling interests | 12 | 5 | 23 | 11
Net income attributable to the Company | $ 332 | $ 531 | $ 1,048 | $ 1,221
Basic weighted average common shares outstanding (in shares) | 507 | 507 | 506 | 507
Dilutive effect of potentially issuable common shares (in shares) | 5 | 5 | 5 | 6
Diluted weighted average common shares outstanding (in shares) | 512 | 512 | 511 | 513
Average stock price used to calculate common stock equivalents (in dollars per share) | $ 95.74 | $ 81.64 | $ 92.14 | $ 82.24

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