Inventory (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Components of inventories
Raw materials	$ 176.1	$ 162.4
Work in process	610.0	605.7
Finished goods	158.5	157.4
Total inventory	944.6	925.5
Inventory, current	931.7	902.7
Inventory, Noncurrent	$ 12.9	$ 22.8

Inventory, net current and noncurrent

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- Definition

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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- Definition

Inventories not expected to be converted to cash, sold or exchanged within the normal operating cycle.

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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.

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- Definition

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.

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