Inventories, net (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Inventories, net
Raw materials	$ 78,055	$ 82,263
Work in process	19,892	14,117
Finished goods (completed systems)	17,688	17,473
Inventories, net	115,635	113,853
Inventory reserves	$ 8,600	$ 8,800

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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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- Definition

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.

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Amount of valuation reserve for inventory.

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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.

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