Acquisitions (Pro-Forma Information) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Business Combinations [Abstract]
Revenue	$ 3,343	$ 3,330
Income from continuing operations	491	509
Net income attributable to the Company	$ 482	$ 492
Basic net income per share:
Basic net income per share - Continuing operations (in dollars per share)	$ 0.92	$ 0.92
Basic net income per share - Net income attributable to the Company (in dollars per share)	0.92	0.91
Diluted net income per share:
Diluted net income per share - Continuing operations (in dollars per share)	0.92	0.91
Diluted net income per share - Net income attributable to the Company (in dollars per share)	$ 0.92	$ 0.90

Business Acquisition, Pro Forma Earnings Per Share, Basic [Abstract]

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Business Acquisition, Pro Forma Earnings Per Share, Diluted [Abstract]

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect per basic share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, per diluted share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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