Inventories - Schedule of Inventories (Details) - USD ($) $ in Millions	Mar. 31, 2020	Sep. 30, 2019
Inventory Disclosure [Abstract]
Finished products	$ 5.3	$ 6.8
Semi-finished products	12.6	11.0
Raw materials and supplies	12.1	8.7
Inventories	$ 30.0	$ 26.5

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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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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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