v3.19.1

QUARTERLY FINANCIAL DATA (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Lower of cost or NRV	$ 930	$ 0	$ 76	$ 705	$ 1,571	$ 666	$ 317	$ 3,825	$ 1,711		$ 6,379		$ 20,374
Costs associated with abnormal production and other													1,707
Gross Margin (Deficit)	14,826	8,959	7,286	7,200	3,628	6,062	4,803	(2,605)	38,271		11,888		(26,797)
Net Income (Loss)	$ 7,634	$ 3,350	$ (958)	$ 1,757	$ (1,636)	$ (1,445)	$ (5,819)	$ (13,667)	11,783		(22,567)		(64,183)
Basic and Diluted Earnings(Loss) Per Share	$ 0.06	$ 0.03	$ (0.01)	$ 0.01	$ (0.01)	$ (0.01)	$ (0.05)	$ (0.17)
Mineral [Member]
Sales	$ 54,364	$ 41,410	$ 55,176	$ 57,320	$ 42,582	$ 36,484	$ 47,347	$ 51,502	208,270	[1]	177,915	[1]	212,097	[1]
Cost of Goods Sold	$ 26,504	$ 23,370	$ 35,426	$ 36,655	$ 26,481	$ 21,414	$ 31,735	$ 38,332	$ 121,955		$ 117,962		$ 169,745
[1] Segment sales include the sales of byproducts generated during the production of potash and Trio®. Prior to the adoption of ASC 606, sales of byproducts were accounted for as a credit to cost of goods sold for potash and Trio®.

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