Inventories - Schedule of Inventories (Details) - USD ($) $ in Millions	Sep. 30, 2019	Sep. 30, 2018
Inventory Disclosure [Abstract]
Finished products	$ 6.8	$ 6.9
Semi-finished products	11.0	8.6
Raw materials and supplies	8.7	8.3
Inventories	$ 26.5	$ 23.8

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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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