Supplemental Financial Information - Property, Plant and Equipment, Net (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Land	$ 166	$ 164
Buildings	3,082	2,842
Machinery, equipment and fixtures	8,454	7,932
Leasehold improvements	216	190
Property, Plant and Equipment, gross	11,919	11,128
Less accumulated depreciation and amortization	5,996	5,469
Property, Plant and Equipment, Net	$ 5,923	$ 5,659

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 of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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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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