Inventories, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Lime and limestone inventories:
Raw materials	$ 3,815	$ 3,232
Finished goods	2,419	2,677
Total	6,234	5,909
Service parts inventories	10,485	9,207
Total inventories	$ 16,719	$ 15,116

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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