Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Components of inventories
Inventory, Gross	$ 60,144	$ 58,215
Inventory Valuation Reserves	(4,784)	(5,328)
Inventories, net	$ 55,360	$ 52,887

Amount of valuation reserve for inventory.

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