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Acquisitions - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Acquired Finite-Lived Intangible Assets [Line Items]
Aggregate purchase price of acquisitions	$ 2,390	$ 2,014
All Other Acquisitions [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Share holder received in cash per share	$ 60.00
Aggregate purchase price of acquisitions	2,375
Intangible assets	969
Weighted average life	19 years
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	817
Weighted average life	20 years
Trademarks [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	58
Weighted average life	15 years
Other intangible Assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 94
Weighted average life	15 years

X

- Definition

Business Acquisition Cash Per Share Paid To Shareholders

+ References

No definition available.

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X

- Definition

Business Acquisition Purchase Price Allocation Intangible Assets

+ References

No definition available.

+ Details

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- Details

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X

- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: 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=26713463&loc=d3e16265-109275

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X

- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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