Inventories (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Inventories
Raw materials	$ 161.1	$ 152.0
Work-in-process	204.6	183.1
Finished goods	95.0	96.6
Demonstration units	57.3	54.5
Inventories	518.0	486.2
Inventory-in-transit	$ 28.5	$ 41.4

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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.

+ References

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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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- Definition

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

+ References

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Gross amount of merchandise, goods, commodities, or supplies to which the entity holds the title and uses for the specific purpose of showing the benefits and features of the entity's products to existing or potential customers.

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Gross amount of merchandise or supplies to which the entity holds the title but does not hold physical possession because the goods are currently being transported.

+ References

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