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Asset Impairments - Identified Intangible Assets, by Major Classification (Detail) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | --- | ---
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | $ 1,472 | $ 6,504 |
Accumulated Amortization | (620) | (3,484) |
Net Book Value | 852 | 3,020 | $ 3,301
Indefinite-lived Trade Names [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 280 | 383 |
Net Book Value | 280 | 383 |
Customer Relationships [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 598 | 4,078 |
Accumulated Amortization | (305) | (2,352) |
Net Book Value | 293 | 1,726 |
Trademarks [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 190 | 891 |
Accumulated Amortization | (123) | (341) |
Net Book Value | 67 | 550 |
Patents [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 121 | 661 |
Accumulated Amortization | (47) | (414) |
Net Book Value | 74 | 247 |
Other [Member] |  |  |
Intangible Assets Net Excluding Goodwill [Line Items] |  |  |
Gross | 283 | 491 |
Accumulated Amortization | (145) | (377) |
Net Book Value | $ 138 | $ 114 |

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