Fixed Assets - Summary of Fixed Assets (Detail) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Property, plant & equipment	$ 28,946	$ 28,386
Less: Accumulated depreciation	22,071	21,779
Fixed assets less accumulated depreciation	$ 6,875	$ 6,607

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
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-Topic 360
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant