Inventories, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Lime and limestone inventories:
Raw materials	$ 4,723	$ 4,546
Finished goods	1,706	1,954
Total	6,429	6,500
Service parts inventories	7,105	6,888
Total inventories	$ 13,534	$ 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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