Inventories - Components of Company's Inventories (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 82	$ 107
Finished goods	225	305
Other	52	54
Total	$ 359	$ 466

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Amount, after of valuation reserves and allowances, of inventory, classified as other, expected to be sold, or consumed within one year or operating cycle, if longer.

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