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v3.20.2

Segments - Additional Information (Detail) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) Segment | Sep. 30, 2019 USD ($)
Segment Reporting Information [Line Items] |  |  |  |
Number of reportable segments | Segment |  |  | 3 |
Inventory Impairments and Other Items [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Charges/ (reversals) | $ 19 |  |  |
Goodwill, Indefinite-lived and Finite-Lived Intangible and Long-Lived Tangible Assets [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Charges/ (reversals) |  |  | $ 1,891 | $ 5,385
Inventory Charges [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Charges/ (reversals) |  | $ 265 | 152 | 571
Severance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Charges/ (reversals) | 23 |  |  |
Severance, Facility Closures And Other Items [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Charges/ (reversals) |  | 37 | $ 144 | 51
Facility Closures [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Charges/ (reversals) | $ 20 |  |  |
Impairment of Long-Lived Tangible Assets [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Charges/ (reversals) |  | $ 12 |  |
Voluntary Early Retirement Program [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Charges/ (reversals) |  |  |  | $ 87

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