Fixed Assets - Summary of Fixed Assets (Detail) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Abstract]
Property, plant & equipment	$ 29,703	$ 29,744
Less: Accumulated depreciation	23,083	22,918
Fixed assets less accumulated depreciation	$ 6,620	$ 6,826

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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- References

No definition available.

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- Definition

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.

+ References

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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