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Summary of Significant Accounting Policies - Identified Intangible Assets by Major Classification (Detail) - USD ($) $ in Millions | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
--- | --- | --- | ---
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | $ 6,320 | $ 6,559 |
Accumulated Amortization | (2,471) | (2,115) |
Net Book Value | 3,849 | 4,444 | $ 5,055
Indefinite-lived Trade Names [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 384 | 536 |
Net Book Value | 384 | 536 |
Customer Relationships [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 4,016 | 4,094 |
Accumulated Amortization | (1,630) | (1,379) |
Net Book Value | 2,386 | 2,715 |
Trademarks [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 880 | 871 |
Accumulated Amortization | (265) | (226) |
Net Book Value | 615 | 645 |
Other [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 1,040 | 1,058 |
Accumulated Amortization | (576) | (510) |
Net Book Value | $ 464 | $ 548 |

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