Inventories (Details) - USD ($) $ in Thousands	Apr. 03, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Raw materials and assembled parts	$ 74,065	$ 56,348
Service inventories, estimated current requirements	13,559	11,556
Work-in-process	82,321	75,710
Finished goods	29,867	26,899
Total current inventories	199,812	170,513
Non-current inventories	$ 54,981	$ 47,109

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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.

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

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date for elements of machinery or equipment held for the purpose of replacing similar parts in the course of repair or maintenance.

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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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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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