Acquisitions (Pro-Forma Information) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Business Combinations [Abstract]
Revenue	$ 3,120	$ 3,207	$ 9,659	$ 9,938
Income from continuing operations	331	305	1,271	1,207
Net income attributable to the Company	$ 326	$ 298	$ 1,239	$ 1,177
Basic net income per share:
Basic net income per share - Continuing operations (in dollars per share)	$ 0.61	$ 0.55	$ 2.32	$ 2.16
Basic net income per share - Net income attributable to the Company (in dollars per share)	0.62	0.55	2.32	2.15
Diluted net income per share:
Diluted net income per share - Continuing operations (in dollars per share)	0.61	0.54	2.30	2.13
Diluted net income per share - Net income attributable to the Company (in dollars per share)	$ 0.61	$ 0.54	$ 2.30	$ 2.12

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)

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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 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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