Inventories (Schedule Of Components Of Inventories) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Inventory, Net [Abstract]
Finished goods	$ 24,632	$ 20,281
Work-in-process	12,046	11,958
Raw materials	36,607	35,909
Stores, supplies and other	19,515	18,759
Total	$ 92,800	$ 86,907

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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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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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of products used directly or indirectly in the manufacturing or production process, which may or may not become part of the final product. May also include items used in the storage, presentation or transportation of physical goods.

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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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