Property, plant and equipment - Property, Plant and Equipment at Cost and Accumulated Depreciation (Details) - USD ($) $ in Millions	Dec. 29, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 48,768	$ 47,776
Less accumulated depreciation	28,250	27,878
Total property, plant and equipment, net	20,518	19,898
Land and leasehold improvements
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	718	795
Building and building equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	12,317	12,375
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	29,444	28,979
Construction in progress
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 6,289	$ 5,627

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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