Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Components of inventories
Inventory, Gross	$ 58,587	$ 58,215
Inventory Valuation Reserves	(4,769)	(5,328)
Inventories, net	$ 53,818	$ 52,887

Amount of valuation reserve for inventory.

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