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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

X

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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