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Acquisitions - Additional Information (Detail) (USD $) | 1 Months Ended | 9 Months Ended
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Aug. 08, 2012 | Sep. 30, 2012 Acquisition
Business Acquisition [Line Items] |  |
Acquisitions completed |  | 12
Aggregate purchase price for Acquisitions |  | $ 2,305,000,000
Intangible assets |  | 597,000,000
Weighted-average life |  | 21 years 1 month 6 days
Cost of acquisition of entity | 2,500,000,000 |
Cash received by shareholders per share | $ 60.00 |
Shares outstanding | 42,400,000 |
Customer relationship [Member] |  |
Business Acquisition [Line Items] |  |
Intangible assets |  | 238,000,000
Weighted-average life |  | 24 years 8 months 12 days
Trademarks [Member] |  |
Business Acquisition [Line Items] |  |
Intangible assets |  | 91,000,000
Weighted-average life |  | 18 years 6 months
Other intangible assets [Member] |  |
Business Acquisition [Line Items] |  |
Intangible assets |  | 268,000,000
Weighted-average life |  | 18 years 8 months 12 days
Goodwill [Member] |  |
Business Acquisition [Line Items] |  |
Intangible assets |  | $ 774,000,000

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- Definition Business Acquisition Upfront Payment For Acquired All Outstanding Equity Shares + References No definition available. + 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Statement of Financial Accounting Standard (FAS) -Number 141 -Paragraph 51 -Subparagraph d -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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