Fixed Assets - Summary of Fixed Assets (Detail) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Property, plant & equipment	$ 30,400	$ 29,965
Less: Accumulated depreciation	23,040	22,725
Fixed assets less accumulated depreciation	$ 7,360	$ 7,240

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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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant