Net Property (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Sep. 30, 2011
Property at cost:
Land and land improvements	$ 39	$ 47
Buildings	251	264
Machinery and equipment	913	897
Company-owned tooling	157	153
Construction in progress	55	74
Total	1,415	1,435
Less accumulated depreciation	(1,011)	(1,014)
Net property	$ 404	$ 421

Carrying amount, as of the balance sheet date, of company-owned tools and dies.

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The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

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- Definition

Gross amount, as of the balance sheet date, of long-lived, depreciable assets that include building structures held for productive use including any addition, improvement, or renovation to the structure, such as interior masonry, interior flooring, electrical, and plumbing.

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Gross amount, at the balance sheet date, of long-lived assets under construction that include construction costs to date on capital projects that have not been completed and assets being constructed that are not ready to be placed into service.

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Carrying amount as of the balance sheet date of real estate held for productive use. This excludes land held for sale.

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Gross amount, as of the balance sheet date, of long-lived, depreciable assets used in the production process to produce goods and services.

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Gross amount, at the balance sheet date, of long-lived physical assets used in the normal conduct of business and not intended for resale. This can include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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Tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year; net of accumulated depreciation. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

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