Inventories - By Category (Details) - USD ($) $ in Millions	Mar. 31, 2019	Mar. 31, 2018
Inventory Disclosure [Abstract]
Finished goods	$ 147.3	$ 134.2
Work in progress	39.8	35.2
Purchased components	76.7	76.0
Raw materials	53.9	53.2
Inventories at First-in, First-Out (FIFO) cost	317.7	298.6
Adjustment to state inventories at Last-in, First-Out (LIFO) cost	(1.2)	5.5
Inventories, net	$ 316.5	$ 304.1

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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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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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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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Gross amount of components used by the entity which are bought from another entity rather than produced by the entity.

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