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Inventories
3 Months Ended
Mar. 31, 2020
Inventories  
Inventories

Note 3. Inventories

Inventories are stated at lower of cost or net realizable value. Cost is determined using a weighted average cost method for raw materials and supplies, and on a first-in, first-out basis for other inventory. Inventory consisted of the following (in thousands):

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March 31,

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December 31,

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2020

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2019

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Raw materials

$

650,140

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$

686,831

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Supplies

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490,401

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498,298

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Work in progress

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160,831

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154,669

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Finished goods

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343,166

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349,245

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Total inventories

$

1,644,538

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$

1,689,043

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