Inventories (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Lime and limestone inventories:
Raw materials	$ 5,986	$ 5,693
Finished goods	2,389	2,283
Total	8,375	7,976
Service parts inventories	5,511us-gaap_OtherInventoryNetOfReserves	5,460us-gaap_OtherInventoryNetOfReserves
Total inventories	$ 13,886us-gaap_InventoryNet	$ 13,436us-gaap_InventoryNet

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 inventories not otherwise specified in the taxonomy.

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