Supplemental Financial Statement Information (Property and Equipment) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	$ 126,462	$ 104,207
Less: accumulated depreciation	(41,713)	(30,561)
Property and equipment, net	84,749	73,646
Land and buildings
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	49,732	39,865
Information technology assets
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	45,906	36,840
Construction in progress
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	23,111	21,036
Leasehold improvements
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	7,516	6,310
Furniture and fixtures
Property, Plant and Equipment, Net [Abstract]
Property and equipment, gross	$ 197	$ 156

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, 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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