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Summary of Significant Accounting Policies - Identified Intangible Assets By Major Classification (Detail) (USD $) In Millions, unless otherwise specified | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
--- | --- | --- | ---
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | $ 6,129 | $ 5,154 |
Accumulated Amortization | (1,386) | (1,081) |
Net Book Value | 4,743 | 4,073 | 4,103
Customer Relationships [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 3,522 | 3,044 |
Accumulated Amortization | (907) | (717) |
Net Book Value | 2,615 | 2,327 |
Trademarks [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 877 | 716 |
Accumulated Amortization | (152) | (122) |
Net Book Value | 725 | 594 |
Trade Names [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 643 | 643 |
Net Book Value | 643 | 643 |
Other Finite Lived Intangible Assets [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 1,087 | 751 |
Accumulated Amortization | (327) | (242) |
Net Book Value | $ 760 | $ 509 |

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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 45 -Subparagraph a(1) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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