Acquisitions (Pro-Forma Information) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Business Combinations [Abstract]
Revenue	$ 3,515	$ 3,460
Net income attributable to the Company	$ 568	$ 481
Basic net income per share:
Basic net income per share attributable to the Company (in dollars per share)	$ 1.10	$ 0.92
Diluted net income per share:
Diluted net income per share attributable to the Company (in dollars per share)	$ 1.09	$ 0.91

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

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

+ References

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- Definition

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=65885119&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 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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