Other Noncurrent Assets and Liabilities - Components of Other Noncurrent Assets in Consolidated Balance Sheets (Details) - USD ($) $ in Millions	Sep. 30, 2019	Sep. 30, 2018
Other Assets Noncurrent [Abstract]
Deferred compensation investments	$ 170	$ 165
Tax and tax indemnity receivables	68	74
Life insurance policies	56	52
Manufacturing catalyst supplies	38	35
Defined benefit plan assets	33	35
Equity and other unconsolidated investments	6	8
Land use rights	6	11
Environmental insurance receivables	12	11
Debt issuance costs	4	6
Other	17	19
Other noncurrent assets, Total	$ 410	$ 416

The legal right to use or benefit from the use of natural resources or access.

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Tax indemnity receivable established as a result of an acquisition of divestiture.

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

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Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Carrying amount as of the balance sheet date of amounts expected to be recovered under the terms of insurance contracts.

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The carrying amount of capitalized costs of materials, supplies, and other assets, which are not included in inventory but used in production.

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Amount of other miscellaneous assets.

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Amount of noncurrent assets classified as other.

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