Summary Of Significant Accounting Policies (Schedule Of Inventory) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Summary Of Significant Accounting Policies [Abstract]
Finished goods	$ 45,127	$ 54,144
Raw materials	16,130	16,795
Work-in-process	9,360	5,544
Supplies and consumables	33,322	30,822
Total	$ 103,939	$ 107,305

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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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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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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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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Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer.

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