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BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Tables) | 6 Months Ended
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Jun. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract] |
Schedule Of Subsidiaries | The unaudited condensed consolidated financial statements include our accounts and the accounts of our wholly-owned and majority-owned subsidiaries, including the following operations as of June 30, 2017:
Name |  | Location |  | Ownership Interest |  | Operation |  | Status of Operations
Northshore |  | Minnesota |  | 100.0% |  | Iron Ore |  | Active
United Taconite |  | Minnesota |  | 100.0% |  | Iron Ore |  | Active
Tilden |  | Michigan |  | 85.0% |  | Iron Ore |  | Active
Empire |  | Michigan |  | 79.0% |  | Iron Ore |  | Indefinitely Idled
Koolyanobbing |  | Western Australia |  | 100.0% |  | Iron Ore |  | Active
Foreign Currency Transaction [Table Text Block] | The following represents the transaction gains and losses resulting from remeasurement for the three and six months ended June 30, 2017 and 2016:
|  | (In Millions)
|  | Three Months Ended June 30, |  | Six Months Ended June 30,
|  | 2017 |  | 2016 |  | 2017 |  | 2016
Remeasurement of short-term intercompany loans |  | $ | 1.5 |  |  | $ | (0.1 | ) |  | $ | 16.6 |  |  | $ | 0.2 |
Remeasurement of cash and cash equivalents |  | (0.5 | ) |  | 0.5 |  |  | (1.7 | ) |  | 1.5 |
Other remeasurement |  | (1.0 | ) |  | (0.2 | ) |  | (1.3 | ) |  | (2.6 | )
Net impact of transaction gains and (losses) resulting from remeasurement |  | — |  |  | 0.2 |  |  | 13.6 |  |  | (0.9 | )

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