Fixed Assets - Summary of Fixed Assets (Detail) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Property Plant And Equipment [Abstract]
Property, plant & equipment	$ 29,022	$ 29,077
Less: Accumulated depreciation	22,668	22,648
Fixed assets less accumulated depreciation	$ 6,354	$ 6,429

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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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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