Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Inventories
Refrigerant and cylinders	$ 65,889	$ 53,593
Less: net realizable value adjustments	(7,100)	(9,133)
Total	$ 58,789	$ 44,460

Amount of inventory reserves for last-in first-out (LIFO) and other inventory valuation methods.

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- Definition

Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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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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