| RELATED PARTIES (Narrative) (Details) | Mar. 31, 2020 | 
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| Hibbing [Member] | |
| Segment Reporting Information [Line Items] | |
| Equity Method Investment, Ownership Percentage | 23.00% | 
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
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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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| X | ||||||||||
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- Details 
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