Acquisitions (Pro-Forma Information) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Business Combinations [Abstract]
Revenue	$ 13,039	$ 12,550	$ 12,202
Income from continuing operations	1,477	1,395	1,222
Net income attributable to the Company	$ 1,471	$ 1,373	$ 1,195
Basic net income per share:
Basic net income per share - Continuing operations (in dollars per share)	$ 2.65	$ 2.49	$ 2.20
Basic net income per share - Net income attributable to the Company (in dollars per share)	$ 2.70	$ 2.50	$ 2.20
Diluted net income per share:
Diluted net income per share - Continuing operations (in dollars per share)	$ 2.62	$ 2.45	$ 2.16
Diluted net income per share - Net income attributable to the Company (in dollars per share)	$ 2.66	$ 2.46	$ 2.16

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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 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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