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Segments - Additional Information (Detail) $ in Millions | 6 Months Ended
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Jun. 30, 2021 USD ($) Segment | Jun. 30, 2020 USD ($)
Segment Reporting Information [Line Items] |  |
Number of reportable segments | Segment | 3 |
Severance, Facility Closures and Inventory Write Downs [Member] |  |
Segment Reporting Information [Line Items] |  |
Charges/ (reversals) | $ 18 |
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) |  | 132
Severance, Facility Closures And Other Items [Member] |  |
Segment Reporting Information [Line Items] |  |
Charges/ (reversals) | $ 42 | $ 102

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