Inventories, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Lime and limestone inventories:
Raw materials	$ 4,800	$ 4,546
Finished goods	2,392	1,954
Total	7,192	6,500
Service parts inventories	7,870	6,888
Total inventories	$ 15,062	$ 13,388

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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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 allowances, as of the balance sheet date of raw materials and finished goods.

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