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v3.10.0.1

DISCONTINUED OPERATIONS (Schedule of Disposal Groups, including Discontinued Operations, Assets and Liabilities) (Details) - USD ($) $ in Millions | Sep. 30, 2018 | Jan. 01, 2018 | Dec. 31, 2017
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Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Current assets of discontinued operations | $ 16.1 | $ 118.5 | $ 118.5
Current liabilities of discontinued operations | 14.2 | $ 75.0 | 75.0
Asia Pacific Iron Ore [Member] |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Cash and cash equivalents | 15.6 |  | 29.4
Accounts receivable, net | 0.0 |  | 33.9
Inventories | 0.0 |  | 45.0
Supplies and other inventories | 0.0 |  | 5.1
Other current assets | 0.5 |  | 5.1
Current assets of discontinued operations | 16.1 |  | 118.5
Property, plant and equipment, net | 0.0 |  | 17.2
Other non-current assets | 0.0 |  | 3.1
Total assets of discontinued operations | 16.1 |  | 138.8
Accounts payable | 4.2 |  | 28.2
Accrued liabilities | 3.0 |  | 28.0
Other current liabilities | 0.0 |  | 15.6
Current liabilities of discontinued operations | 7.2 |  | 71.8
Environmental and mine closure obligations | 0.0 |  | 28.8
Other liabilities | 9.3 |  | 23.4
Total liabilities of discontinued operations | $ 16.5 |  | $ 124.0

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