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Segments - Additional Information (Detail) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2020 Segment
Segment Reporting Information [Line Items]
Number of reportable segments | Segment					3
Severance, Inventory Impairments, Facility Closures and Other Items [Member]
Segment Reporting Information [Line Items]
Charges/ (reversals)	$ 102
Goodwill, Indefinite-lived and Finite-Lived Intangible and Long-Lived Tangible Assets [Member]
Segment Reporting Information [Line Items]
Charges/ (reversals)		$ 1,891	$ 5,373
Inventory Charges [Member]
Segment Reporting Information [Line Items]
Charges/ (reversals)		114	302
Severance, Facility Closures And Other Items [Member]
Segment Reporting Information [Line Items]
Charges/ (reversals)		$ 18	5	$ 11
Voluntary Early Retirement Program [Member]
Segment Reporting Information [Line Items]
Charges/ (reversals)			$ 89

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- 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.

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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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