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Acquisitions and Investments - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2012 Acquisition | Dec. 31, 2011 Acquisition | Dec. 31, 2010 Acquisition
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Aggregate purchase price of acquisitions | $ 500 |  |
Intangible assets |  | 273 |
Weighted average life | 5 years |  |
All Other Acquisitions [Member] |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Acquisitions completed | 17 | 9 | 12
Aggregate purchase price of acquisitions | 2,880 | 1,038 | 556
Intangible assets | 981 | 273 | 299
Weighted average life | 18 years | 16 years | 18 years
Customer Relationships [Member] |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Intangible assets | 473 | 119 | 116
Weighted average life | 20 years | 14 years | 15 years
Trademarks [Member] |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Intangible assets | 159 | 39 | 59
Weighted average life | 16 years | 35 years | 30 years
Other intangible Assets [Member] |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Intangible assets | 348 | 115 | 124
Weighted average life | 17 years | 12 years | 15 years
Goodwill [Member] |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Intangible assets | $ 1,000 |  |

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- Definition Business Acquisition Purchase Price Allocation Intangible Assets + References No definition available. + Details
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- Details
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- 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=7658586&loc=d3e16265-109275 + Details
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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. + Details
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- Definition The number of businesses acquired by the entity during the period. + References No definition available. + Details
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