Net Property (Details) - USD ($) $ in Millions	Mar. 31, 2020	Sep. 30, 2019
Property, Plant and Equipment [Line Items]
Property at cost	$ 1,407	$ 1,400
Less: accumulated depreciation	(898)	(885)
Net property	509	515
Land and land improvements
Property, Plant and Equipment [Line Items]
Property at cost	31	31
Buildings
Property, Plant and Equipment [Line Items]
Property at cost	223	224
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property at cost	960	935
Company-owned tooling
Property, Plant and Equipment [Line Items]
Property at cost	141	136
Construction in progress
Property, Plant and Equipment [Line Items]
Property at cost	$ 52	$ 74

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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