v3.19.1

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES DISAGGREGATION OF REVENUE (Details) - USD ($) $ 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
Mineral [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
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]
Potash [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales |  |  |  |  |  |  |  |  | 107,471 |  | 95,540 |  | 149,335 |
Trio [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales |  |  |  |  |  |  |  |  | 64,139 |  | 63,338 |  | 52,884 |
Water [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales |  |  |  |  |  |  |  |  | 19,797 |  | 7,042 |  | 0 |
Salt [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales |  |  |  |  |  |  |  |  | 6,877 |  | 6,334 |  | 2,947 |
Magnesium Chloride [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales |  |  |  |  |  |  |  |  | 6,804 |  | 5,432 |  | 6,931 |
Brines [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales |  |  |  |  |  |  |  |  | 1,777 |  | 229 |  | 0 |
Other [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales |  |  |  |  |  |  |  |  | $ 1,405 |  | $ 0 |  | $ 0 |
[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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