Acquisitions (Pro-Forma Information) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Business Combinations [Abstract]
Revenue	$ 2,935	$ 2,883	$ 9,192	$ 9,057
Income from continuing operations	260	247	1,076	947
Net income attributable to the Company	$ 253	$ 242	$ 1,058	$ 926
Basic net income per share:
Basic net income per share - Continuing operations (in dollars per share)	$ 0.46	$ 0.44	$ 1.92	$ 1.70
Basic net income per share - Net income attributable to the Company (in dollars per share)	$ 0.46	$ 0.44	$ 1.93	$ 1.70
Diluted net income per share:
Diluted net income per share - Continuing operations (in dollars per share)	$ 0.46	$ 0.44	$ 1.89	$ 1.68
Diluted net income per share - Net income attributable to the Company (in dollars per share)	$ 0.45	$ 0.44	$ 1.90	$ 1.67

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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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