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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
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Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Earnings Per Share [Abstract] |  |  |  |
Net income before non-controlling interests | $ 536 | $ 507 | $ 1,232 | $ 1,085
Less: Net income attributable to non-controlling interests | 5 | 6 | 11 | 15
Net income attributable to the Company | $ 531 | $ 501 | $ 1,221 | $ 1,070
Basic weighted average common shares outstanding (in shares) | 507.0 | 514.0 | 507.0 | 514.0
Dilutive effect of potentially issuable common shares (in shares) | 5.0 | 6.0 | 6.0 | 7.0
Diluted weighted average common shares outstanding (in shares) | 512.0 | 520.0 | 513.0 | 521.0
Average stock price used to calculate common stock equivalents (in dollars per share) | $ 81.64 | $ 75.41 | $ 82.24 | $ 73.36
Stock options outstanding (in shares) | 10.5 | 12.4 | 10.5 | 12.4

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