Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Net Components of Inventory
Raw materials	$ 324,935	$ 310,204
Work in process	242,181	191,660
Finished goods	186,739	205,814
Less: Excess and obsolete reserve	(73,664)	(73,807)
Inventories, net	$ 680,191	$ 633,871

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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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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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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