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Acquisitions - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified | 6 Months Ended
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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 |

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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=26713463&loc=d3e16265-109275 + Details
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- 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 + Details
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