Inventories, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Lime and limestone inventories:
Raw materials	$ 3,398	$ 4,279
Finished goods	2,752	2,866
Total	6,150	7,145
Service parts inventories	8,473	8,065
Total inventories	$ 14,623	$ 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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