Fixed Assets - Summary of Fixed Assets (Detail) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Property, Plant and Equipment [Abstract]
Property, plant & equipment	$ 30,039	$ 29,573
Less: Accumulated depreciation	22,640	22,214
Fixed assets less accumulated depreciation	$ 7,399	$ 7,359

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
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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