Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Components of inventories
Inventory, Gross	$ 59,467	$ 60,500
Inventory Valuation Reserves	(4,557)	(4,595)
Inventories, net	$ 54,910	$ 55,905

Amount of valuation reserve for inventory.

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