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DISCONTINUED OPERATIONS DISCONTINUED OPERATIONS Schedule of Disposal Groups, including Discontinued Operations, Assets and Liabilities - Asia Pacific Iron Ore (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Jan. 01, 2018 | Dec. 31, 2017
--- | --- | --- | ---
Current assets of discontinued operations | $ 12.4 | $ 118.5 | $ 118.5
Current liabilities of discontinued operations | 6.7 | $ 75.0 | 75.0
Asia Pacific Iron Ore [Member] |  |  |
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents | 12.4 |  | 29.4
Disposal Group, Including Discontinued Operation, Accounts Receivable, Net | 0.0 |  | 33.9
Disposal Group, Including Discontinued Operation, Inventory | 0.0 |  | 45.0
Disposal group, including Discontinued Operations, Supplies and other inventories | 0.0 |  | 5.1
Disposal Group, Including Discontinued Operation, Other Assets, Current | 0.0 |  | 5.1
Current assets of discontinued operations | 12.4 |  | 118.5
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment | 0.0 |  | 17.2
Disposal Group, Including Discontinued Operation, Other Assets, Noncurrent | 0.0 |  | 3.1
Disposal Group, Including Discontinued Operation, Assets | 12.4 |  | 138.8
Disposal Group, Including Discontinued Operation, Accounts Payable | 3.4 |  | 28.2
Disposal Group, Including Discontinued Operation, Accrued Liabilities | 0.4 |  | 28.0
Disposal Group, Including Discontinued Operation, Other Liabilities, Current | 0.0 |  | 15.6
Current liabilities of discontinued operations | 3.8 |  | 71.8
Disposal Group, Including Discontinued Operations, Environmental and mine closure obligations | 0.0 |  | 28.8
Disposal Group, Including Discontinued Operation, Other Liabilities | 8.3 |  | 23.4
Disposal Group, Including Discontinued Operation, Liabilities | $ 12.1 |  | $ 124.0

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