Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Components of inventories
Inventory, Gross	$ 60,668	$ 60,500
Inventory Valuation Reserves	(4,486)	(4,595)
Inventories, net	$ 56,182	$ 55,905

Amount of valuation reserve for inventory.

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