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Goodwill and Intangible Assets - Identified Intangible Assets by Major Classification (Detail) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | --- | ---
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | $ 6,504 | $ 6,444 |
Accumulated Amortization | (3,484) | (3,143) |
Net Book Value | 3,020 | 3,301 | $ 3,530
Indefinite-lived Trade Names [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 383 | 384 |
Net Book Value | 383 | 384 |
Customer Relationships [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 4,078 | 4,074 |
Accumulated Amortization | (2,352) | (2,118) |
Net Book Value | 1,726 | 1,956 |
Trademarks [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 891 | 885 |
Accumulated Amortization | (341) | (317) |
Net Book Value | 550 | 568 |
Patents [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 661 | 602 |
Accumulated Amortization | (414) | (384) |
Net Book Value | 247 | 218 |
Other [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 491 | 499 |
Accumulated Amortization | (377) | (324) |
Net Book Value | $ 114 | $ 175 |

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