Inventories - Schedule of Inventory (Details) - USD ($) $ in Millions	Jun. 30, 2018	Sep. 30, 2017
Inventory Disclosure [Abstract]
Finished products	$ 202	$ 180
Raw materials, supplies and work in process	34	31
LIFO reserves	(37)	(33)
Obsolete inventory reserves	(3)	(3)
Inventories	$ 196	$ 175

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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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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Amount of valuation reserve for inventory.

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The aggregate carrying amount as of the balance sheet date of items held by the entity which are partially completed at the time of measurement and unprocessed items that will go through the production process and become part of the final product. Includes supplies used directly or indirectly in the manufacturing or production process. This element may be used when the reporting entity combines work in process and raw materials into an aggregate amount.

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