Inventories, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Lime and limestone inventories:
Raw materials	$ 4,495	$ 4,279
Finished goods	2,713	2,866
Total	7,208	7,145
Service parts inventories	8,201	8,065
Total inventories	$ 15,409	$ 15,210

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

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