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Acquisitions and Investments (Details Textual) (USD $) In Millions, unless otherwise specified	1 Months Ended	12 Months Ended
	Sep. 30, 2009	Dec. 31, 2011 Acquisitions Y	Dec. 31, 2010 Acquisitions Y	Dec. 31, 2009 Y Acquisitions
Acquisitions and Investments (Textual) [Abstract]
Aggregate purchase price of acquisitions			$ 500
Intangible assets		273
Weighted average life		5
Other Acquisitions [Member]
Acquisitions and Investments (Textual) [Abstract]
Number of acquisitions		9	12	9
Aggregate purchase price of acquisitions		1,038	556	573
Percentage of IntelliServ operations sold	45.00%
Intangible assets		131	299	115
Weighted average life		16	18	11
Customer Relationships [Member]
Acquisitions and Investments (Textual) [Abstract]
Intangible assets		119	116	60
Weighted average life		14	15	9
Trademarks [Member]
Acquisitions and Investments (Textual) [Abstract]
Intangible assets		39	59	46
Weighted average life		35	30	18
Other Intangible Assets [Member]
Acquisitions and Investments (Textual) [Abstract]
Intangible assets		$ 115	$ 124	$ 9
Weighted average life		12	15	7

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- Definition

Number of acquisitions.

+ References

No definition available.

+ Details

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- Definition

Percentage Of Operations Sold.

+ References

No definition available.

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- Definition

The calculated weighted-average amortization period of a major class of finite-lived intangible assets acquired during the current period either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 44

-Subparagraph a(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16265-109275

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- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 52

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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