Inventories (Details) - USD ($) $ in Millions	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Inventories
Raw materials and supplies	$ 204.4		$ 200.2
Work in process	128.4		157.9
Finished goods	54.1		54.1
Total inventories, gross	386.9		412.2
Progress payments	0.0		(1.4)
Reduction to LIFO cost basis	(9.3)		(10.6)
Total inventories, net	$ 377.6	$ 375.4	$ 400.2

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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Amount of advances received from customers under long-term contracts which have been offset against inventories accounts at the balance sheet date.

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