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SEGMENT REPORTING (Narrative) (Details) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 USD ($) | Sep. 30, 2018 USD ($) | Sep. 30, 2019 USD ($) unit | Sep. 30, 2018 USD ($)
Segment Reporting Information [Line Items] |  |  |  |
Number of Reporting Units | unit |  |  | 2 |
Revenues | $ 555.6 | $ 741.8 | $ 1,455.8 | $ 1,636.1
SALES MARGIN | 154.9 | 261.6 | 448.8 | 607.6
Mining and Pelletizing [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Revenues | 555.6 | 741.8 | 1,455.8 | 1,636.1
SALES MARGIN | $ 154.9 | $ 261.6 | $ 448.8 | $ 607.6

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