Fixed Assets (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Land	$ 773	$ 292
Buildings and improvements	7,067	4,978
Machinery, tools and equipment	15,994	12,936
Other, including assets under construction	2,512	1,871
Fixed assets	26,346	20,077
Accumulated depreciation	(11,384)	(9,755)
Fixed assets, net	14,962	10,322
Depreciation	$ 1,767	$ 1,191	$ 945
Land Buildings And Improvements [Member] \| Minimum [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	12 years
Land Buildings And Improvements [Member] \| Maximum [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	45 years
Machinery And Equipment [Member] \| Minimum [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Machinery And Equipment [Member] \| Maximum [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	20 years

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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