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Segments - Additional Information (Detail) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2020 USD ($) Segment | Mar. 31, 2019 USD ($)
Segment Reporting Information [Line Items] |  |
Number of reportable segments | Segment | 3 |
Charges/ (reversals) | $ 2,023 | $ 11
Goodwill, Indefinite-lived and Finite-Lived Intangible and Long-Lived Tangible Assets [Member] |  |
Segment Reporting Information [Line Items] |  |
Charges/ (reversals) | 1,891 |
Inventory Charges [Member] |  |
Segment Reporting Information [Line Items] |  |
Charges/ (reversals) | 114 | 11
Severance, Facility Closures And Other Items [Member] |  |
Segment Reporting Information [Line Items] |  |
Charges/ (reversals) | $ 18 | $ 11

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