v3.19.1

BUSINESS SEGMENTS (Narrative) (Details) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2018 Reporting_Segments | Dec. 31, 2018 Reporting_Segments | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Segment Reporting [Abstract] |  |  |  |
Number of reportable segments | Reporting_Segments | 2 | 3 |  |
Segment Reporting Information [Line Items] |  |  |  |
Restructuring charges |  |  | $ 266 | $ 2,723
Operating Segments [Member] | Potash [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Restructuring charges |  |  |  | 2,100
Operating Segments [Member] | Trio [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Restructuring charges |  |  |  | 400
Corporate [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Restructuring charges |  |  |  | $ 200

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