RELATED PARTIES (Narrative) (Details) $ in Millions |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
|
Jun. 30, 2016
USD ($)
|
Jun. 30, 2017
Facility
|
Jun. 30, 2016
USD ($)
|
Mar. 31, 2017
USD ($)
|
Mar. 31, 2016
USD ($)
|
|
| U.S. Iron Ore [Member] | Ìý | Ìý | Ìý | Ìý | Ìý |
| Segment Reporting Information [Line Items] | Ìý | Ìý | Ìý | Ìý | Ìý |
| Number of mines (in number of facilities) | Facility | Ìý | 4 | Ìý | Ìý | Ìý |
| Joint Venture Partners [Member] | U.S. Iron Ore [Member] | Ìý | Ìý | Ìý | Ìý | Ìý |
| Segment Reporting Information [Line Items] | Ìý | Ìý | Ìý | Ìý | Ìý |
| Number of mines (in number of facilities) | Facility | Ìý | 2 | Ìý | Ìý | Ìý |
| Empire [Member] | Arcelor Mittal [Member] | Ìý | Ìý | Ìý | Ìý | Ìý |
| Segment Reporting Information [Line Items] | Ìý | Ìý | Ìý | Ìý | Ìý |
| Subsequent Paid Distributions of Partners' Equity Amounts | Ìý | Ìý | Ìý | $ 8.7 | $ 11.1 |
| Recorded Distributions of Partners' Equity Amounts | $ 24.4 | Ìý | $ 41.4 | Ìý | Ìý |
| Paid Distributions of Partners' Equity Amounts | $ 17.0 | Ìý | $ 17.0 | Ìý | Ìý |
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- Definition Number of mines No definition available.
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- Definition Paid Distributions of Partners' Equity Amounts No definition available.
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- Definition Recorded Distributions of Partners' Equity Amounts No definition available.
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- Definition Subsequent Paid Distributions of Partners' Equity Amounts No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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