Property, Plant and Equipment - Components of Property, Plant and Equipment in Consolidated Balance Sheets (Details) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2019
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 3,265	$ 3,165
Accumulated depreciation	(1,700)	(1,588)
Net property, plant and equipment	1,565	1,577
Land [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Gross	150	148
Buildings [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Gross	489	461
Machinery and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Gross	2,433	2,361
Construction in Progress [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 193	$ 195

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, 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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