Inventories (Schedule of Inventory) (Details) - USD ($) $ in Millions	Oct. 01, 2018	Sep. 30, 2018	Sep. 30, 2017
Inventory Disclosure [Abstract]
Finished goods		$ 125.4	$ 120.0
Work in process		21.2	15.7
Raw materials, supplies and other		249.5	223.0
Total FIFO Cost		396.1	358.7
Less: Excess of FIFO cost over LIFO cost		0.0	(23.3)
Inventories	$ 396.1	$ 396.1	$ 335.4

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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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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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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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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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

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