Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Components of inventory
Raw materials and parts	$ 121,265	$ 118,790
Work-in-progress	50,186	43,035
Finished goods	98,596	93,565
Total Inventory, Net	$ 270,047	$ 255,390

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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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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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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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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