Fixed Assets - Summary of Fixed Assets (Detail) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Property Plant And Equipment [Abstract]
Property, plant & equipment			$ 28,568	$ 28,386
Less: Accumulated depreciation			21,877	21,779
Fixed assets less accumulated depreciation	$ 6,691	$ 6,607	$ 6,691	$ 6,607

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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