Supplemental Balance Sheet Information - PP&E (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Property, plant and equipment - at cost
Property and equipment, at cost	$ 26,124	$ 24,873
Less: Accumulated depreciation	(16,791)	(16,135)
Property, Plant and Equipment - net	9,333	8,738
Land
Property, plant and equipment - at cost
Property and equipment, at cost	351	340
Buildings and leasehold improvements
Property, plant and equipment - at cost
Property and equipment, at cost	7,877	7,564
Machinery and equipment
Property, plant and equipment - at cost
Property and equipment, at cost	16,586	15,776
Construction in progress
Property, plant and equipment - at cost
Property and equipment, at cost	$ 1,310	$ 1,193

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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