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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
--- | ---
Mar. 31, 2018 | Mar. 31, 2017
Earnings Per Share [Abstract] |  |
Net income before non-controlling interests | $ 696 | $ 578
Less: Net income attributable to non-controlling interests | 6 | 9
Net income attributable to the Company | $ 690 | $ 569
Basic weighted average common shares outstanding (in shares) | 508.0 | 515.0
Dilutive effect of potentially issuable common shares (in shares) | 6.0 | 7.0
Diluted weighted average common shares outstanding (in shares) | 514.0 | 522.0
Average stock price used to calculate common stock equivalents (in dollars per share) | $ 82.83 | $ 71.32
Stock options outstanding (in shares) | 10.6 | 12.8

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- Definition Amount after tax of income (loss) from continuing operations attributable to the parent. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.13) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4613673-111683 + Details
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- Definition Amount after tax of income (loss) from continuing operations attributable to the noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4569616-111683 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4568447-111683 + Details
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